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Idle's fine but dont run fine when I give gas... by Andreeas
Started on: 05-14-2014 03:37 PM
Replies: 29 (314 views)
Last post by: donnie072003 on 07-20-2014 09:19 PM
Andreeas
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Report this Post05-14-2014 03:37 PM Click Here to See the Profile for AndreeasClick Here to Email AndreeasSend a Private Message to AndreeasEdit/Delete MessageReply w/QuoteDirect Link to This Post
Have a peoblem with my 2.8 V6.
It idle's fine, but if I try to give some gas it runs bad. Seems like its loosing power. Only way to keep it running (except when its idleing) is to pump with the gaspedal. But after some pumping it backfires.
Seems like some gas wont fire, gathers up and then fires...
Is it possible that its bad compression?
Could it be the ICM?

------------------
/Andreéas

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Sabenn_88_notch
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Report this Post05-14-2014 03:52 PM Click Here to See the Profile for Sabenn_88_notchClick Here to Email Sabenn_88_notchSend a Private Message to Sabenn_88_notchEdit/Delete MessageReply w/QuoteDirect Link to This Post
have you had timing problems with it in the past or did this just come up?
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2.5
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Report this Post05-15-2014 09:36 AM Click Here to See the Profile for 2.5Send a Private Message to 2.5Edit/Delete MessageReply w/QuoteDirect Link to This Post
I wouls not think compression or ICM, but what else has happened to the car recently..etc...?

Some ideas, fuel filter could be clogging, it is regular maintinance to replace that. Catalytic converter could be clogging. Fuel pressure good?

[This message has been edited by 2.5 (edited 05-15-2014).]

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phonedawgz
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Report this Post05-15-2014 10:22 AM Click Here to See the Profile for phonedawgzClick Here to visit phonedawgz's HomePageClick Here to Email phonedawgzSend a Private Message to phonedawgzEdit/Delete MessageReply w/QuoteDirect Link to This Post
Check your fuel pressure
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NW-Fiero
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Report this Post05-15-2014 10:47 AM Click Here to See the Profile for NW-FieroSend a Private Message to NW-FieroEdit/Delete MessageReply w/QuoteDirect Link to This Post
To my knowledge compression problems don't just "happen" unless there is a major event the caused it. But you could check the 1-3-5 easy enough and check the Distributor ( coil,ICM, rotor, cap, pick-up) , plugs, wires. As they say "Rule out the Easy Stuff First" O'Reillys/Autozone will test the ICM while you wait..for "FREE"

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Mark
' 85 2m6 3.4PR
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Gall757
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Report this Post05-15-2014 11:18 AM Click Here to See the Profile for Gall757Send a Private Message to Gall757Edit/Delete MessageReply w/QuoteDirect Link to This Post
 
quote
Originally posted by NW-Fiero:
O'Reillys/Autozone will test the ICM while you wait..for "FREE"



ummmm....we are talking Sweden here....Maybe it's Sven O'Reilly, but I doubt it.

edit: +1 on fuel pressure.

[This message has been edited by Gall757 (edited 05-15-2014).]

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Csjag
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Report this Post05-15-2014 12:00 PM Click Here to See the Profile for CsjagClick Here to Email CsjagSend a Private Message to CsjagEdit/Delete MessageReply w/QuoteDirect Link to This Post
I agree, likely suspect is the fuel pump
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IROCTAFIERO
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Report this Post05-15-2014 12:54 PM Click Here to See the Profile for IROCTAFIEROSend a Private Message to IROCTAFIEROEdit/Delete MessageReply w/QuoteDirect Link to This Post
fuel pump/filter
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NW-Fiero
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Report this Post05-15-2014 04:49 PM Click Here to See the Profile for NW-FieroSend a Private Message to NW-FieroEdit/Delete MessageReply w/QuoteDirect Link to This Post
Jag är ledsen, jag borde ha tittat på informationen i sidhuvudet. Det måste finnas en AuotParts hus i området som testar elektriska komponenter ... Var är du på väg att köpa en bränslepump om det är det som är problemet??


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Mark
' 85 2m6 3.4PR
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Andreeas
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Report this Post07-17-2014 03:50 AM Click Here to See the Profile for AndreeasClick Here to Email AndreeasSend a Private Message to AndreeasEdit/Delete MessageReply w/QuoteDirect Link to This Post
The car had been sitting for about 12-13 years when I finally got it running.. Initially the car just died up on the earlier owner... Many things checked after that..

In short;
Changed ICM ang sparkplugs/cables/coil for 2 years ago. Since I removed the dirstibutor doing this I have had som issues with timing the spark/engine again. Not really sure if its really ok. I've tried to get info about it but I'm not really sure. I'm curious about the exact mounting for the distributor. Supposed to be some marks to match between the distributor and the block, but I'm not sure I found them.

Yesterday we checked compression - was good in all cylinders.. about 7,5 - 8 in each.
With the ALDL A+B connected we timed at 10 degress. The symptom is as described earlier. The car runs great in idle. If I give gas it first sounds like it loses power, it then raises in RPM. If I do this several times/for a longer time than some seconds - it backfires.
When I took away the A-B - loop (with the engine running) the car died immediately. Is that ok? To me it is a sign the timing is not ok..

New fuelpump (stock in tank) last summer.
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Patrick
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Report this Post07-17-2014 03:59 AM Click Here to See the Profile for PatrickClick Here to Email PatrickSend a Private Message to PatrickEdit/Delete MessageReply w/QuoteDirect Link to This Post
 
quote
Originally posted by Andreeas:

To me it is a sign the timing is not ok..


Make sure the outer hub of the harmonic balancer has not spun. The thick timing mark should line up with actual TDC of cylinder #1.

If the hub has spun, your timing will be all out of whack. Time it by ear and see how the engine runs. Just don't leave it too far advanced. Back it off if you hear "pinging" when going up a hill in 4th gear.

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Andreeas
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Report this Post07-17-2014 04:04 AM Click Here to See the Profile for AndreeasClick Here to Email AndreeasSend a Private Message to AndreeasEdit/Delete MessageReply w/QuoteDirect Link to This Post
Is this something that can just happen? As far as I know no-one has disassemblied the block or something since it ran last time.

Checked with a timing-light yesterday and with the A+B connected the timing was ok... And it ran nice...
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Patrick
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Report this Post07-17-2014 04:10 AM Click Here to See the Profile for PatrickClick Here to Email PatrickSend a Private Message to PatrickEdit/Delete MessageReply w/QuoteDirect Link to This Post
 
quote
Originally posted by Andreeas:

Checked with a timing-light yesterday and with the A+B connected the timing was ok... And it ran nice...


What do you mean "it ran nice"? What's the problem then?

 
quote
Originally posted by Andreeas:

Is this something that can just happen? As far as I know no-one has disassemblied the block or something since it ran last time.


The harmonic balancer is not within the block. The timing marks are on its outer hub. There's a rubber "donut" of sorts between the outer and inner hub. The rubber deteriorates over time (these cars are more than 25 years old), and then the outer hub begins to move independently of the inner hub.

I suspect this problem is a lot more common than many people realize.

[This message has been edited by Patrick (edited 07-17-2014).]

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Andreeas
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Report this Post07-17-2014 04:13 AM Click Here to See the Profile for AndreeasClick Here to Email AndreeasSend a Private Message to AndreeasEdit/Delete MessageReply w/QuoteDirect Link to This Post
It ran nice means it idle'd fine when in limp-home-mode...

okay, so the timing marks could have moved, but in that way the car wouldnt run even in limp-home-mode. If the timing marks moved some degrees, the car would run, but not smooth... Am I right?
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Andreeas
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Report this Post07-17-2014 04:19 AM Click Here to See the Profile for AndreeasClick Here to Email AndreeasSend a Private Message to AndreeasEdit/Delete MessageReply w/QuoteDirect Link to This Post
I´d really like a picture or something exactly how the distributor is supposed to be when I have found the TDC. Have had it explained in english, but I really dont get it.
Anyone ever took a picture in that state??..
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Patrick
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Report this Post07-17-2014 04:23 AM Click Here to See the Profile for PatrickClick Here to Email PatrickSend a Private Message to PatrickEdit/Delete MessageReply w/QuoteDirect Link to This Post
 
quote
Originally posted by Andreeas:

It ran nice means it idle'd fine when in limp-home-mode...


Do you want to leave it in "limp-home-mode"? I suspect not.

 
quote
Originally posted by Andreeas:

okay, so the timing marks could have moved, but in that way the car wouldnt run even in limp-home-mode.


Sure it could. Depends how far the outer hub has spun.

 
quote
Originally posted by Andreeas:

If the timing marks moved some degrees, the car would run, but not smooth... Am I right?


The timing marks themselves mean nothing. They're just a reference. If the plugs are firing at the right time in relation to where the pistons are, the engine is happy. I time my engines by ear, but not everyone is comfortable doing that. If you use a timing light, then yes, the timing marks need to be in the right place... which they're not if the hub has spun. So sure, you might be able to get the engine running with the timing off, but no, it's not going to be smooth and/or have proper power.


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Patrick
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Report this Post07-17-2014 04:31 AM Click Here to See the Profile for PatrickClick Here to Email PatrickSend a Private Message to PatrickEdit/Delete MessageReply w/QuoteDirect Link to This Post
 
quote
Originally posted by Andreeas:

I´d really like a picture or something exactly how the distributor is supposed to be when I have found the TDC.


It's not quite that simple because the distributor rotor also needs to be pointing correctly. There is an "ideal" position for the rotor and distributor, and this image has been posted here many times... but it's past 1:30 AM locally, and I'm going to bed.

[This message has been edited by Patrick (edited 07-17-2014).]

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Patrick
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Report this Post07-17-2014 04:36 AM Click Here to See the Profile for PatrickClick Here to Email PatrickSend a Private Message to PatrickEdit/Delete MessageReply w/QuoteDirect Link to This Post

Patrick

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Member since Apr 99

One last word... a spun harmonic balancer may not be your problem, but I just wanted you to be aware of the possibility. Read This thread.
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Andreeas
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Report this Post07-17-2014 04:40 AM Click Here to See the Profile for AndreeasClick Here to Email AndreeasSend a Private Message to AndreeasEdit/Delete MessageReply w/QuoteDirect Link to This Post
Thanks Patrick...

No I dont want to leave it in limp-home but thats the way to set the timing....

What I mean is that if the timing marks havent moved more than it can run in limp-home then it should be running in normal mode...
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Andreeas
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Report this Post07-18-2014 11:11 AM Click Here to See the Profile for AndreeasClick Here to Email AndreeasSend a Private Message to AndreeasEdit/Delete MessageReply w/QuoteDirect Link to This Post
Have searched the forum but I cant find picture of the distributor and how it will be matched with marks / prongs / springs (and whatever you call it in english) when timing the ignition?? :-) ..

Anyone knows where to find pics???
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Report this Post07-18-2014 11:26 AM Click Here to See the Profile for 2.5Send a Private Message to 2.5Edit/Delete MessageReply w/QuoteDirect Link to This Post
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Report this Post07-18-2014 12:15 PM Click Here to See the Profile for S-toonSend a Private Message to S-toonEdit/Delete MessageReply w/QuoteDirect Link to This Post
Do you have any codes?

Sounds like what happend to me once, can't remember what I was doing to my car but I must have hit the MAP Sensor, and the plug came lose.

It would idle fine, but when I tried to drive it, it was basically like it wouldn't want to go no matter how much I pressed the gas, no power, took it around the block, barely as it was very very slow, basically crawling lol and when got home, I checked to see if there was any codes. Sure enough I had a code saying it was the MAP Sensor, code 33 or 34 can't remember exactly, anyway I take a look at the MAP Sensor, and yeah the plug wasn't even hooked up. Plugged it back in, made sure the vacuum hose was on there good too, took it for a ride and it was back to normal.
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Andreeas
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Report this Post07-18-2014 06:07 PM Click Here to See the Profile for AndreeasClick Here to Email AndreeasSend a Private Message to AndreeasEdit/Delete MessageReply w/QuoteDirect Link to This Post
Seen the vis several times and as I remember it doesnt show how the dist should be installed.

No codes shown by SES light (only 12 = normal)
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Report this Post07-18-2014 06:36 PM Click Here to See the Profile for tsharkSend a Private Message to tsharkEdit/Delete MessageReply w/QuoteDirect Link to This Post
..

[This message has been edited by tshark (edited 09-08-2018).]

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Andreeas
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Report this Post07-18-2014 06:48 PM Click Here to See the Profile for AndreeasClick Here to Email AndreeasSend a Private Message to AndreeasEdit/Delete MessageReply w/QuoteDirect Link to This Post
Havent checked fuel pressure cause I imstalled new fuelpump last summer, but will check this as soon as I can borrow tools formit.

Rotor and cap is pretty new, 2 years. Changed these same time as other ignition-parts. Looks fine. I'm more eorried if they are "trimmed" right...

So pics would be nice...

------------------
/Andreéas

[This message has been edited by Andreeas (edited 07-18-2014).]

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Patrick
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Report this Post07-20-2014 03:26 AM Click Here to See the Profile for PatrickClick Here to Email PatrickSend a Private Message to PatrickEdit/Delete MessageReply w/QuoteDirect Link to This Post
 
quote
Originally posted by Andreeas:

Rotor and cap is pretty new, 2 years. Changed these same time as other ignition-parts. Looks fine. I'm more eorried if they are "trimmed" right...

So pics would be nice...


You mean "timed" right. Don't worry, my Swedish sucks.

Okay, just for you I took a picture of my own engine for this thread. The double green lines represent the best angle for the distributor to be set up at. And you'll also notice I've indicated which terminal is for #1. Obviously the rotor needs to be pointing at that location when #1 cylinder is at top dead center of the compression stroke. It might be necessary to unbolt the distributor, pull it up, turn the rotor and drop the distributor back down again. This might also involve turning the oil pump a bit if things don't align properly (as the oil pump and distributor work together). If you haven't done this before, it may sound like a complicated job, but it's not really.

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Report this Post07-20-2014 10:19 AM Click Here to See the Profile for BlacktreeClick Here to visit Blacktree's HomePageClick Here to Email BlacktreeSend a Private Message to BlacktreeEdit/Delete MessageReply w/QuoteDirect Link to This Post
 
quote
Originally posted by Andreeas:

Havent checked fuel pressure cause I imstalled new fuelpump last summer, but will check this as soon as I can borrow tools formit.

When you replaced the fuel pump, did you also replace the short hose that attaches to the top of the pump? That little hose is known to fail and cause low fuel pressure. Also, the fuel pressure regulator can fail and cause low fuel pressure. And if the fuel filter gets clogged, that can also cause low fuel pressure.

Good luck!
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Report this Post07-20-2014 11:58 AM Click Here to See the Profile for BloozberrySend a Private Message to BloozberryEdit/Delete MessageReply w/QuoteDirect Link to This Post
Also, you shouldn't overlook the possibility that your Throttle Position Sensor (TPS) may be malfunctioning. If you're not sure where it is or how to test it, post back here and I or someone else can guide you.
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Andreeas
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Report this Post07-20-2014 06:29 PM Click Here to See the Profile for AndreeasClick Here to Email AndreeasSend a Private Message to AndreeasEdit/Delete MessageReply w/QuoteDirect Link to This Post
Patrick: thanks for the pic!! How nice of you...

Blacktree: didnt replace the hose cause I didnt know it could be a problem (hadnt heard/read that earlier)
Regulator not replaced either.. Same cause...
Think I replaced the fuel filter but I'm not really sure right now. Will have to check if I bought one. IF I did, then its replaced.

Bloozberry: TPS was tested and worked fine last year...

I will have tomdo some homework now:
Timing the ignition
Check fuelpressure
Check compression the RIGHT way
Check TPS again

Thanks tomall of you this far..
Will come back as soon as Imhave done my hw...

------------------
/Andreéas

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donnie072003
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Report this Post07-20-2014 09:19 PM Click Here to See the Profile for donnie072003Click Here to visit donnie072003's HomePageClick Here to Email donnie072003Send a Private Message to donnie072003Edit/Delete MessageReply w/QuoteDirect Link to This Post
Check your injector fuses. You could be running on just one bank of injectors. Both fuses are 5 amp and located in the fuse box under the dash.
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