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4.9 idle air control motor by jeffndebrus
Started on: 03-18-2009 09:01 PM
Replies: 42 (1362 views)
Last post by: paulcal on 08-22-2013 11:47 PM
jeffndebrus
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Report this Post03-18-2009 09:01 PM Click Here to See the Profile for jeffndebrusSend a Private Message to jeffndebrusEdit/Delete MessageReply w/QuoteDirect Link to This Post
4.9 idle air control motor

I am having an idle problem. The car idles very high when first started- 1700rpms for a minute then it suddenly drops to 1000rpms and then it surges back and forth several times before settling in at around 1100rpms. I can take my foot off the gas pedal and the car is happy traveling down the road at 30mph. I changed the ecm-no change. I am using a Rockcrawl modified chip.

I also noticed tonight that when I turn the car off the iac motor continues plunging in and out for about 30 seconds.

We replaced the iac a year ago due to an idle surge at a stop light that almost launched us into traffic.

Any ideas?

Edit to add that the last time we drove it in a group someone called to ask why we kept slowing down. Our speed was off by 15mph. Not sure if a bad vss signal could cause any of this?

[This message has been edited by jeffndebrus (edited 03-18-2009).]

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Report this Post03-18-2009 09:46 PM Click Here to See the Profile for hobodude34Click Here to Email hobodude34Send a Private Message to hobodude34Edit/Delete MessageReply w/QuoteDirect Link to This Post
automatic? check your grounds..then Check them again.... just to be sure.. most of the 4.9 idle motors get sluggish after so many years.. is it setting a code for it?
edit to add: mine did the same thing... plundged back and forth for a min when the key was turned off...i had some bad connections in the c203 where the two plugs fit together the connections became loose and not making good contact..

[This message has been edited by hobodude34 (edited 03-18-2009).]

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Report this Post03-18-2009 09:48 PM Click Here to See the Profile for josef644Click Here to Email josef644Send a Private Message to josef644Edit/Delete MessageReply w/QuoteDirect Link to This Post
Read this thread. It is all about idle problems on the 4.9. The cure is there also

//www.fiero.nl/forum/A...050119-2-049097.html
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jeffndebrus
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Report this Post03-18-2009 10:33 PM Click Here to See the Profile for jeffndebrusSend a Private Message to jeffndebrusEdit/Delete MessageReply w/QuoteDirect Link to This Post
where do you place the leads from your multimeter to read the measurements in the following post:

This is awesome...positive points given!!!!!!!!
I stayed home from work today and did the idle learn procedure again with this info and the car runs fantastic, no more fighting, no more jumping until you reach five mph while slowing down. Just awesome.
Where you set the idle to 525rpm in the procedure set it to 400 to 450rpm(I set mine to 400rpm.)
Set the TPS sensor to read 5.5 volts at this rpm. Then kill the motor, do this by smothering the throttle body, the key has to stay on. Move out the IAC plunger by crossing the plug like you did to move it in and screw in the plunger until it reads 1.15 to 1.2 volts(I did mine to 1.16 volts.). Turn off the key, wait 20 seconds turn on key,don't start car now,just turn key to on, now turn it off again. Start car and idle until temp comes up to 176degs. then idle in park for ten minutes, put foot on brake, put car in drive and idle for three more minutes. Turn off the car. Unhook the positive battery cable for 10 to 15 seconds to initiate the idle learn and go for a ride. I instantly had the sail on condition fixed and the car comes to a stop with no fighting whatsoever.

Thank you to 87fastback for the info and the solution to my problem, hopefully it works for everyone else.....
Thank you to Cplensdorf for bringing back this post...

Dragon1/Brian
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Report this Post03-18-2009 10:52 PM Click Here to See the Profile for jscott1Send a Private Message to jscott1Edit/Delete MessageReply w/QuoteDirect Link to This Post
Just so you know, on the 4.9 it's called an Idle Speed Control or ISC motor. I've followed the procedure and so far it hasn't worked for me.

The Manual Transmission version of the 4.9 may or may not have a worse problem with sail on but everyone I've talked to with a manual has found it to be more noticeable.
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Report this Post03-19-2009 05:24 AM Click Here to See the Profile for jeffndebrusSend a Private Message to jeffndebrusEdit/Delete MessageReply w/QuoteDirect Link to This Post
Now I'm screwed

after spraying both screws that hold the idle position sensor with PB Blaster

they both broke off instead of backing out
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Report this Post03-19-2009 10:44 AM Click Here to See the Profile for jscott1Send a Private Message to jscott1Edit/Delete MessageReply w/QuoteDirect Link to This Post
 
quote
Originally posted by jeffndebrus:

Now I'm screwed

after spraying both screws that hold the idle position sensor with PB Blaster

they both broke off instead of backing out


Do you mean the throttle position sensor?

You should be able to drill out the broken screws without damaging the threads.
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quote
Originally posted by jeffndebrus:

where do you place the leads from your multimeter to read the measurements in the following post:

This is awesome...positive points given!!!!!!!!
I stayed home from work today and did the idle learn procedure again with this info and the car runs fantastic, no more fighting, no more jumping until you reach five mph while slowing down. Just awesome.
Where you set the idle to 525rpm in the procedure set it to 400 to 450rpm(I set mine to 400rpm.)
Set the TPS sensor to read 5.5 volts at this rpm. Then kill the motor, do this by smothering the throttle body, the key has to stay on. Move out the IAC plunger by crossing the plug like you did to move it in and screw in the plunger until it reads 1.15 to 1.2 volts(I did mine to 1.16 volts.). Turn off the key, wait 20 seconds turn on key,don't start car now,just turn key to on, now turn it off again. Start car and idle until temp comes up to 176degs. then idle in park for ten minutes, put foot on brake, put car in drive and idle for three more minutes. Turn off the car. Unhook the positive battery cable for 10 to 15 seconds to initiate the idle learn and go for a ride. I instantly had the sail on condition fixed and the car comes to a stop with no fighting whatsoever.

Thank you to 87fastback for the info and the solution to my problem, hopefully it works for everyone else.....
Thank you to Cplensdorf for bringing back this post...

Dragon1/Brian


Ideally you want to use a scanner to read the voltage readings. Not sure which leads you would use as I have always used my scanner - I know not much help. I will suggest that you set the base idle as low as you can get it without the motor stalling if you are using a manual transaxle - set the recommend rpm with an automatic.

Sucks about the screws breaking, hopefully you can get them out without too much trouble.

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jeffndebrus
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Report this Post03-19-2009 02:56 PM Click Here to See the Profile for jeffndebrusSend a Private Message to jeffndebrusEdit/Delete MessageReply w/QuoteDirect Link to This Post
Today was a very SCARY day!

I went through the idle learn procedure as documented time after time after time after time.

Each time the car would react appropriately idle set to 525---reconnect isc motor cycle key 2 times--idle in park 10 min--idle in drive with brake on 3 minutes. Idle would settle in right at 650rpms.

But each time I would begin to drive down the road after about 10 minutes the isc motor would step all the way out and the car would be going 80mph with NO gas pedal. It did this to me probably 5-6 times--once at a traffic light I was holding the brake down with all my might and the car was burning rubber and moving into the intersection.

I changed the ecm/ changed the isc motor------I have run out of time and I guess I will not be at Daytona this year unless I can drive the car with the isc motor unplugged.

[This message has been edited by jeffndebrus (edited 03-19-2009).]

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Mickey_Moose
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Report this Post03-19-2009 04:33 PM Click Here to See the Profile for Mickey_MooseClick Here to visit Mickey_Moose's HomePageClick Here to Email Mickey_MooseSend a Private Message to Mickey_MooseEdit/Delete MessageReply w/QuoteDirect Link to This Post
WOW, that would definity cause major concerns. Are you getting and codes??

The VSS shouldn't cause this, I would think more a temp sensor or wiring loose or maybe the ECM is losing the tach signal. Do you have the ability to monitor the sensors (scanner)? Do you have another chip you could try?
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Report this Post03-19-2009 04:56 PM Click Here to See the Profile for josef644Click Here to Email josef644Send a Private Message to josef644Edit/Delete MessageReply w/QuoteDirect Link to This Post
I don't think you set the voltage to the Cadillac Service bullitan specs that I sent you the above link to. In 1993 Cadillac sent out a revision, and it should be set to .55 volts, because of this"Sail On" threw the intersections problem. If you have it set to 5.5 volts it is not correct. Please read my link. The other guys all having this problem solved it using this method.
Quoted from: 87fastback 8-26-2004
Group Ref.: Engine

Bulletin No.: 316006A

Date: November, 1993

SUBJECT:
SLOW DECELERATION WITH CLOSED THROTTLE ABOVE 5 MPH
(READJUST AIR RATE)

MODELS:
1990-93 CADILLAC DEVILLES, ELDORADOS, FLEETWOODS, SEVILLES, AND SIXTY SPECIALS (EQUIPPED WITH 4.5L OR 4.9L ENGINES)

THIS BULLETIN IS BEING REVISED TO CORRECT THE WARRANTY STATEMENT, AND CANCELS AND SUPERSEDES BULLETIN 316006 PUBLISHED OCTOBER, 1993.

Some owners may comment about slow deceleration with closed throttle above 5 mph. This may be particularly noticeable after performing bulletin T-93-44 (Corporate bulletin 016540R) even though all engine adjustments have been set according to published service information.

To correct this condition readjust the minimum air rate to between 400 and 450 rpm, the TP Sensor setting to .55 volts, and reset TP Sensor/idle learns using the procedures listed in the appropriate Service Information Manual.

For warranty purposes use:

Labor Operation: J6358

Good Luck

Joe
Edited to add:
It sure would not hurt anything to try this procedure out Cadillac published. What you are doing now is not working

[This message has been edited by josef644 (edited 03-19-2009).]

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jeffndebrus
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Report this Post03-19-2009 05:52 PM Click Here to See the Profile for jeffndebrusSend a Private Message to jeffndebrusEdit/Delete MessageReply w/QuoteDirect Link to This Post
Thank you,
the paper I printed out was using .50volts not .55 but I don't think that would make this much difference.
Maybe I will try again one more time in the morning. This is extremely disappointing and Very dangerous.

My auto X ray seems to be broken---it won't take my vin and gives me a bunch of Chinese looking characters. I left it in the car and I guess the Florida sun was too much for it.

I do have a nice digital multimeter to test voltage with though. But I admit I was trying to push the test leads through the wire insulation instead of stripping some insulation back like I should so my reading may have been off.

Somehow I suspect there is something else wrong----not sure--just a gut feeling.

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josef644
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Report this Post03-19-2009 07:20 PM Click Here to See the Profile for josef644Click Here to Email josef644Send a Private Message to josef644Edit/Delete MessageReply w/QuoteDirect Link to This Post
Well, I was going bu what you posted above:

" plunger until it reads 1.15 to 1.2 volts(I did mine to 1.16 volts."

I know there is a big difference between 1.16 and .50 volts.

I hope you find your cure, cause I am about 30 days behind you on this swap. I want all the bugs found and repaired before I get there.
Please be sure and post your results so the rest of us can learn.
Joe Crawford

[This message has been edited by josef644 (edited 03-19-2009).]

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Fieroseverywhere
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Report this Post03-19-2009 08:57 PM Click Here to See the Profile for FieroseverywhereClick Here to Email FieroseverywhereSend a Private Message to FieroseverywhereEdit/Delete MessageReply w/QuoteDirect Link to This Post
 
quote
Originally posted by jeffndebrus:

But each time I would begin to drive down the road after about 10 minutes the isc motor would step all the way out and the car would be going 80mph with NO gas pedal. It did this to me probably 5-6 times--once at a traffic light I was holding the brake down with all my might and the car was burning rubber and moving into the intersection.



Ok this is going to sound odd...

If your car does this again press the throttle. The ISC only controls idle when the throttle switch is closed (foot off gas pedal). If you press the gas pedal the PCM stops sending the signals to the ISC. It should at the very least be easier to press the brake and gas to hold the car still then to fight the PCM and ISC. I'd bet your ISC plunger is out of adjustment also. It shouldn't be able to push you to 80mph.

From the service manual...

 
quote

Idle Speed Control (ISC)

The Idle Speed Control is mounted on the throttle body and is used to control idle speed. The ISC plunger acts as as movable throttle stop changing throttle valve angle. The PCM monitors engine idle speed and moves the ISC plunger (throttle stop) to maintain desired idle required for operating condition.
An integral part of the ISC is the throttle switch. The position of the throttle switch determines whether or not the ISC controls idle. When the throttle lever rests against the ISC plunger, the switch contacts are closed and the PCM moves the ISC plunger to the programmed idle speed position. When the throttle lever breaks contact with the ISC plunger, the switch contacts open and the PCM stops sending idle speed commands. Engine speed is again controlled by the accelerator pedal.


Now for my take on the problem. 1: The throttle switch inside the ISC is not working correctly if the ISC is doing anything while the gas pedal is pressed. Replace the ISC if this is the case. Opening up the ISC and cleaning the contacts for the throttle switch may work also. I'm on my 3rd ISC now with only 1000 miles on my car. They are not the most durable item thats for sure.

2: I think you probably need to redo the TPS/Idle learn procedure including min idle set also. Idle as low as possible with ISC fully retracted (throttle lever sitting on min idle screw). Set TPS to .55 volts. With ISC fully extended TPS voltage should read 1.15-1.2 volts. (NOTE: The ISC plunger will click and retract slightly when it reaches full extension (this is why there is a range for the voltage). Extend it to the point just before it clicks. You want it to extend as far as possible or it will throw off the settings.) If the TPS voltage is not between 1.15-1.2 at ISC full extension then turn the ISC plunger screw down til it is (snap the throttle plate to be sure the setting sticks also). Retract ISC full, check TPS voltage again. Does is still say .55 volts (it should)? Extend ISC one more time to double check for TPS voltage 1.15-1.2. Now you can complete the rest of the procedure.

I wanted to add something too. If your car has AC (I'm sure in florida you do ) make sure you turn it on while idling in park. The PCM needs to the see the extra load to properly set idle under those conditions.

I would send Jon at fieroaddiction.com an e-mail also. Make sure that desired idle was not set higher in the PROM. This is often done in manual 4.9's (cause you don't want the idle dropping to 800rpm while shifting) and could have been changed by mistake. He keeps records for PROMs he's sold to be able to double check things like this. Mine is set to 1100rpm for the manual. While in motion (VSS above 5mph) the RPM will not drop below 1100.

Unfortunately the CTS, MAT, and MAP can all effect idle speed also. So if nothing else works start checking sensors though I really think your problem is elsewhere.

Hope this was some help and not me just blabing. I wish you the best of luck. Stay safe.

[This message has been edited by Fieroseverywhere (edited 03-19-2009).]

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jscott1
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Report this Post03-19-2009 09:11 PM Click Here to See the Profile for jscott1Send a Private Message to jscott1Edit/Delete MessageReply w/QuoteDirect Link to This Post
 
quote
Originally posted by jeffndebrus:

Today was a very SCARY day!

once at a traffic light I was holding the brake down with all my might and the car was burning rubber and moving into the intersection.




That is scary...

Here's a tip. If this happens again, put the car in Neutral. It might be a little scary getting it back in gear. but it will give things a chance to settle down without pushing you into the intersection.

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Report this Post03-19-2009 09:30 PM Click Here to See the Profile for josef644Click Here to Email josef644Send a Private Message to josef644Edit/Delete MessageReply w/QuoteDirect Link to This Post
I like the press the throttle peddle a bit idea. Makes good since when you think about it.
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Report this Post03-19-2009 09:33 PM Click Here to See the Profile for jeffndebrusSend a Private Message to jeffndebrusEdit/Delete MessageReply w/QuoteDirect Link to This Post
yea,
I was repeatedly pushing the pedal to the floor and releasing it when it happened hoping to unstick something, but I could hear the idle control motor tapping tapping tapping as it continued to try to push out further. It's like the car is possessed!

We built this car several years ago and it didn't always have this problem. It had a new harness bought from Ed Parks Fiero factory/ a Rockcrawl chip. It utilizes the 4t60e that was attached to the caddy engine when I pulled it.

I do have an extra chip from a caddy but it has not been programmed for the Fiero. Odd that ED Parks says you don't have to reprogram--everyone else says yes you do. Not sure if I should try it or not.

I'm going to strip the insulation off the tps a bit and make sure I have good contact with my multimeter probes.---Try again I guess. I will also replace the tps as I have a spare out there.
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Report this Post03-19-2009 09:36 PM Click Here to See the Profile for jeffndebrusSend a Private Message to jeffndebrusEdit/Delete MessageReply w/QuoteDirect Link to This Post

jeffndebrus

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Member since Aug 2001
 
quote
Originally posted by jscott1:


That is scary...

Here's a tip. If this happens again, put the car in Neutral. It might be a little scary getting it back in gear. but it will give things a chance to settle down without pushing you into the intersection.


Yea did that a few times too but had to shift into neutral and shut it down quickly because it would rev free and I didn't want to damage the engine.
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Report this Post03-19-2009 09:39 PM Click Here to See the Profile for jeffndebrusSend a Private Message to jeffndebrusEdit/Delete MessageReply w/QuoteDirect Link to This Post

jeffndebrus

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quote
Originally posted by josef644:

Read this thread. It is all about idle problems on the 4.9. The cure is there also

//www.fiero.nl/forum/A...050119-2-049097.html


Joe,
I appreciate this link--it is indeed this link that you provided that I used to print and had with me in the car today,
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Report this Post03-19-2009 10:01 PM Click Here to See the Profile for FieroseverywhereClick Here to Email FieroseverywhereSend a Private Message to FieroseverywhereEdit/Delete MessageReply w/QuoteDirect Link to This Post
 
quote
Originally posted by jeffndebrus:

yea,
I was repeatedly pushing the pedal to the floor and releasing it when it happened hoping to unstick something, but I could hear the idle control motor tapping tapping tapping as it continued to try to push out further. It's like the car is possessed!

We built this car several years ago and it didn't always have this problem. It had a new harness bought from Ed Parks Fiero factory/ a Rockcrawl chip. It utilizes the 4t60e that was attached to the caddy engine when I pulled it.

I do have an extra chip from a caddy but it has not been programmed for the Fiero. Odd that ED Parks says you don't have to reprogram--everyone else says yes you do. Not sure if I should try it or not.

I'm going to strip the insulation off the tps a bit and make sure I have good contact with my multimeter probes.---Try again I guess. I will also replace the tps as I have a spare out there.


You only want to press the pedal enough for the throttle plate to clear the ISC plunger. This should make the PCM stop controlling the ISC.

The extra chip you have may not work. It probably has the VATS still active on it. If you don't have the bypass its useless. You don't have to reprogram the chip but you will need to do other things if you don't.

Just double check the TPS idle learn. I'd bet that will solve you problem. At the least it will make it better. Make sure to use the setting in the service bulliten josef644 posted above. They differ from the FSM and what posted in most of that thread and it makes a big difference. Basically the service bulliten made it possible to shorten the length of the ISC plunger while keeping idle relatively the same. Even at full extension the ISC will not be able to raise idle to as high as you saw today. Keep the faith... you'll get it working.

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Report this Post03-20-2009 01:54 PM Click Here to See the Profile for jeffndebrusSend a Private Message to jeffndebrusEdit/Delete MessageReply w/QuoteDirect Link to This Post
Yes each time it happened the idle was over 3000rpms.

And after I shut the engine down the stepping motor was still tapping and trying to extend the plunger out further.

Back on my 12hr nightshift but maybe I can try 1 more time before Daytona.

Rereading the tech service bulletin and------I don't think our 4.9 will idle at 450rpms---but will try.

[This message has been edited by jeffndebrus (edited 03-20-2009).]

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Report this Post03-20-2009 10:17 PM Click Here to See the Profile for FierokingClick Here to visit Fieroking's HomePageClick Here to Email FierokingSend a Private Message to FierokingEdit/Delete MessageReply w/QuoteDirect Link to This Post
I am going to throw out another part of the problem. I had the same problems with my 4.9 both standard and with the Allante Intake. The final part of the problem for my car was the O2 sensor. When I did my install I replaced the O2 sensor with an after market (Schuck's) unit. This was a direct replacement Bosch sensor. I finally found a article here on the Forum that stated that the Bosch units did not work for the 4.9. After exhausting all other ideas and doing the Idle procedure enough times to the point were I could do it in my sleep. I finally bit the bullet and purchased the much more expensive AC Delco O2 sensor for my car. The change was immediate. My car idles at 650 rpm's does not run rich, and I have no sail on problems. I have a Rockcrawl chip in my car and it has be a joy to drive for the last 3 plus years.

Hope this helps. Also do set the voltage to .55 volts it does make a difference

Joe Sokol

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Report this Post03-23-2009 05:44 PM Click Here to See the Profile for jeffndebrusSend a Private Message to jeffndebrusEdit/Delete MessageReply w/QuoteDirect Link to This Post
Tried for several more hours today---

The lowest reading I can get on the tps pressed hard against the screw is .60volts, when the isc motor is retracted and not touching the throttle. However, when I power the isc motor extending the plunger---the tps voltage is not nearly enough. Extending the plunger by turning out the screw--the screw fell out of the plunger before I reached 1.1volts on the tps. So, restarting the threads just enough to hold the screw in the plunger I am at about .96volts. I followed the idle learn from there BUT the isc plunger has now pushed the minimum idle to about 1600rpms. If I manually turn the screw back in to the plunger I can achieve the desired 650rpms--but feel like something is wrong.

On my wiring there is three wires feeding the tps. Black/blue/grey. Black is apparently the ground. Backprobing the grey wire gives a constant 5 volts. The blue wire voltage changes with throttle changes so that is where I took my readings.

Frustrated !
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Report this Post03-24-2009 10:21 AM Click Here to See the Profile for jeffndebrusSend a Private Message to jeffndebrusEdit/Delete MessageReply w/QuoteDirect Link to This Post
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Report this Post03-24-2009 01:22 PM Click Here to See the Profile for KentoClick Here to Email KentoSend a Private Message to KentoEdit/Delete MessageReply w/QuoteDirect Link to This Post
 
quote
Originally posted by jeffndebrus:

bump


OK I can only give you moral support from an old friend. You already know what my fix would be heeheheheheh PN 4412

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Found a Red 84 4speed, Waiting to get a house so I can re-home it
There are Two kinds of Fiero's : Notchies and Donors!

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Mickey_Moose
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Report this Post03-24-2009 03:53 PM Click Here to See the Profile for Mickey_MooseClick Here to visit Mickey_Moose's HomePageClick Here to Email Mickey_MooseSend a Private Message to Mickey_MooseEdit/Delete MessageReply w/QuoteDirect Link to This Post
Is there room if you remove the tps sensor and file the holes out longer to give you a bit more adjustment? This seems a bit odd that you don't have enough travel - how does the linkage look on the other side? Possible that the shaft may have slipped (turned) and is not sitting with the proper orientaion? Been a while since I paid that close attention to the throttle body.

As for the wire to read off of, that is the one I would use (you have power (feed and ground) and the signal wire). I would set the idle screw (base rpm) as low as you can without the car stalling - I can normally get about 450 rpm's - doesn't idle very well, but it does stay running.

Also, it's been a while since I read the original instructions but in the step where you are to stop the motor running, I have been told that it is better to stall out the motor vs. turning the key off. I have been told to stuff a large rag into the throttle body to choke off the air, for some reason that does nto seem to work for me (maybe my rag was too pourous or something), so I just pull the fuel pump fuse.

Now, I am not so sure that this will solve your original problem with the car reving up on it's own while driving - but it can't hurt to try.

Keep us posted.

[This message has been edited by Mickey_Moose (edited 03-24-2009).]

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jeffndebrus
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Report this Post03-25-2009 03:22 PM Click Here to See the Profile for jeffndebrusSend a Private Message to jeffndebrusEdit/Delete MessageReply w/QuoteDirect Link to This Post
Last night I replaced a rear caliper and hose because my previous attempts to stop the car from going through a red light apparently exacerbated a hose failure resulting in a caliper that wouldn't release and a smoking wheel when I limped home.

Ok: The latest---I had to use larger screws to hold the tps in so that is why it will only go down to .60

Last night I could hear what sounded like electrical arcing short but could not see it. This also was causing the engine to stumble. I Believe that this could have also caused the idle speed controller to keep pushing the plunger further and further out. Upon further investigating I found that I could duplicate the noise (arcing) when I tapped the icm with the butt of a screwdriver.

I unplugged the idle control motor --set the idle for 650rpms and took a long drive with all conditions of stop and go and several interstate runs. The car runs reasonably well without the icm (warm Fl weather+my a/c is not hooked up) so I will probably take it to Daytona as is.

Since I already changed the idle control motor I will have to also check the wiring harness which was original and not replaced with the Ed Parks harness. I suspect that a little more fooling around and replacement of a few parts should fix it as designed.

Wish I could have spent this time redoing my headliner/ installing my new dewwipes/ waxing the car------Oh Well.

[This message has been edited by jeffndebrus (edited 03-25-2009).]

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josef644
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Report this Post03-25-2009 05:11 PM Click Here to See the Profile for josef644Click Here to Email josef644Send a Private Message to josef644Edit/Delete MessageReply w/QuoteDirect Link to This Post
I am happy to hear that it worked pretty good just unplugging it. Hoping your Daytona trip is smooth and uneventfull going and coming. Nice looking Notchie!!!
Joe

[This message has been edited by josef644 (edited 03-25-2009).]

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jeffndebrus
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Report this Post03-25-2009 07:59 PM Click Here to See the Profile for jeffndebrusSend a Private Message to jeffndebrusEdit/Delete MessageReply w/QuoteDirect Link to This Post
 
quote
Originally posted by Kento:


OK I can only give you moral support from an old friend. You already know what my fix would be heeheheheheh PN 4412



Ahhhh Yes, the venerable dirt circle track 2 barrel 500cfm Holley Carburetor #4412.
http://www.amazon.com/gp/product/B0006HKNM2

But since I paid $700 for a harness I better keep bangin away at this problem--lol

[This message has been edited by jeffndebrus (edited 03-25-2009).]

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stickpony
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Report this Post03-26-2009 03:12 PM Click Here to See the Profile for stickponyClick Here to visit stickpony's HomePageSend a Private Message to stickponyEdit/Delete MessageReply w/QuoteDirect Link to This Post
if you were in south FL, i'd help you out. anyways, you can hit up my phone if you want to pick my brain, i have had more than my fair share of bad ISC motors on a 4.9L, and have gotten through every situation with flying colors.

Aaron
561-201-6191
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jeffndebrus
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Report this Post03-31-2009 12:09 PM Click Here to See the Profile for jeffndebrusSend a Private Message to jeffndebrusEdit/Delete MessageReply w/QuoteDirect Link to This Post
I wonder if this is my underlying problem???



Apparently, my ecm is commanding an idle of 1350? Maybe Rockcrawl set mine for a standard tranny?
Here's another wierd thing---with all that has gone on--no codes have been set.

[This message has been edited by jeffndebrus (edited 03-31-2009).]

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sanderson
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Report this Post03-31-2009 01:06 PM Click Here to See the Profile for sandersonClick Here to Email sandersonSend a Private Message to sandersonEdit/Delete MessageReply w/QuoteDirect Link to This Post
 
quote
Originally posted by jeffndebrus:

I wonder if this is my underlying problem???



Apparently, my ecm is commanding an idle of 1350? Maybe Rockcrawl set mine for a standard tranny?
Here's another wierd thing---with all that has gone on--no codes have been set.




My Auto X-ray scan tool indicates a higher commanded idsle speed than I actual see. My 4.9 is idling OK. I think this is an anomaly in the scan tool or PCM - don't think it's your problem.
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jeffndebrus
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Report this Post03-31-2009 05:31 PM Click Here to See the Profile for jeffndebrusSend a Private Message to jeffndebrusEdit/Delete MessageReply w/QuoteDirect Link to This Post
I don't know??? I wrote Rockcrawl--maybe I will hear back from him and maybe I won't. He goes missing for months at a time.


The only code I am setting now is a park/neutral error ?????????


Also, I found a huge mistake that I made previously. I had my tps set at .05 instead of .55. I have corrected that and the car is running much better except for the higher idle.
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Mickey_Moose
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Report this Post04-04-2009 01:19 PM Click Here to See the Profile for Mickey_MooseClick Here to visit Mickey_Moose's HomePageClick Here to Email Mickey_MooseSend a Private Message to Mickey_MooseEdit/Delete MessageReply w/QuoteDirect Link to This Post
I threw the scanner on my car today and the target idle was 1224 (or something like that) - but was running and idling fine - mine idles @ 800 due to Rockcrawl setting it up as a standard - I believe this is the idle that he changes, not the target one.

my tps was reading .58 at idle as well with a MAT @ 213.4°

...if that helps any...
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jeffndebrus
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Report this Post04-04-2009 04:17 PM Click Here to See the Profile for jeffndebrusSend a Private Message to jeffndebrusEdit/Delete MessageReply w/QuoteDirect Link to This Post
Hey Mickey Moose
thanks for that info. I wrote Rockcrawl twice but did not hear back.
Things are much better since I corrected the tps at idle to .55 and it cured the transmission from what it had started to do as well. After setting the tps incorrectly, the tranny started acting up when I would decelerate at all it felt like it was coming out of gear-tcc or whatever. That is fixed now.
I will run through the idle learn once more for good luck.
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Mickey_Moose
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Report this Post04-05-2009 08:57 AM Click Here to See the Profile for Mickey_MooseClick Here to visit Mickey_Moose's HomePageClick Here to Email Mickey_MooseSend a Private Message to Mickey_MooseEdit/Delete MessageReply w/QuoteDirect Link to This Post
Sure no problem - I just was waiting for some sort of decent weather to get the car out. With the automatic, your car should idle at 600 rpms IIRC once it is setup and warm.
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josef644
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Report this Post07-07-2009 04:02 PM Click Here to See the Profile for josef644Click Here to Email josef644Send a Private Message to josef644Edit/Delete MessageReply w/QuoteDirect Link to This Post
Jeff did you ever get this corrected and working right?
Joe
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jeffndebrus
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Report this Post07-09-2009 10:44 AM Click Here to See the Profile for jeffndebrusSend a Private Message to jeffndebrusEdit/Delete MessageReply w/QuoteDirect Link to This Post
Not as of yet,
We drove it to Daytona with the isc unplugged and other than having to throttle a little at start up it ran fine.

I have a coolant sensor problem I believe which could be part of this? Our radiator cooling fan does not come on unless we set our climate control in the a/c position. The temp guage works on the dash. This could be affecting the isc if I remember correctly.

The car has essentially sat in the driveway since Daytona and now the fuel pump I installed just before Daytona is bad. Guess I'll be dropping the tank again.
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josef644
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Report this Post07-09-2009 10:47 AM Click Here to See the Profile for josef644Click Here to Email josef644Send a Private Message to josef644Edit/Delete MessageReply w/QuoteDirect Link to This Post
Jeff what pump did you put in it? I dont want to get one of the ones for mine that only last under 180 days.
Joe
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BigGuyTinyCar
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Report this Post02-18-2011 02:21 AM Click Here to See the Profile for BigGuyTinyCarClick Here to Email BigGuyTinyCarSend a Private Message to BigGuyTinyCarEdit/Delete MessageReply w/QuoteDirect Link to This Post
This is an old thread, but since jeff has the 4.9 and he says he has the Injection Technology harness, his CTS is most
likely not hooked up to the ECM. (see //www.fiero.nl/forum/F.../HTML/114347.html#p0 ). That shouldn't cause the weird acceleration problems he is (was) seeing, but will need to be corrected nonetheless before doing any idle adjustments.
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