Pennock's Fiero Forum
  Technical Discussion & Questions
  Car won't start (Page 1)

Post New Topic  Post A Reply
Email This Page to Someone! | Printable Version

This topic is 2 pages long:  1   2 
Previous Page | Next Page
next newest topic | next oldest topic
Car won't start by Andreeas
Started on: 09-12-2011 05:34 PM
Replies: 50 (867 views)
Last post by: Gall757 on 07-28-2013 10:01 AM
Andreeas
Member
Posts: 65
From: Huskvarna, Sweden
Registered: Aug 2011


Feedback score: N/A
Leave feedback

Rate this member

Report this Post09-12-2011 05:34 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
I'm sorry to bother you all with this but I think I have read a lot of threads about similar problems and I just can't get it...

Got an -87 Fiero from my father-in-law last year. From the beginning there was an 2,5 litre ironduke but he swapped it into a 2,8 litre V6. One day (about ten years ago) the car died while running and since that day they couldn't make it run again. I don't really know exactly what they have tested/checked before but I know that theres is a pretty new pick-up coil now.

I can fire it up on start-gas and have had it running for about 20 secs (on start-gas), then it dies (probably because of bad mixture gas/air??) The enginge doesn't run really smooth like I think it should - but it does run. The sparks and wires / rotor / cap / coil are old so maybe it would run better with som new ignition-parts.

When I try to start without start-gas the tach reaches 400 rpm. I can hear the fuelpump work for 2 secs everytime I start to crank and the fuelpressure was ok when I checked last year (when I got the car). The car won't start immediate. I always have to crank several times, then turn key off - crank again - turn key off (this time it sounds like it's near to fire up ) - then crank again. When I have cranked for a while the car runs for about 5 secs, then it dies again.

I have read a lot of threads here on PFF about similar problems and it seems that the ICM can be the problem. Is it possible that the ICM is dysfunctional even though it fires up after cranking several times? Or is it more likely something with the ECM / injectors? Grounding? Is it possible that the the engine can run for about 5-7 secs on start gas squirt from the cold start injector??

I've checked:
Injector fuses - OK
Rear injectors sounds when cranking (is ticking) and has 12V with key on
No engine trouble codes

For sure I've checked more things but I just can't remember right now.

Does anyone have any suggestions what to do?


------------------
/Andreéas

[This message has been edited by Andreeas (edited 09-12-2011).]

IP: Logged
PFF
System Bot
Gall757
Member
Posts: 10738
From: Holland, MI
Registered: Jun 2010


Feedback score: N/A
Leave feedback





Total ratings: 89
Rate this member

Report this Post09-12-2011 05:48 PM Click Here to See the Profile for Gall757Send a Private Message to Gall757Edit/Delete MessageReply w/QuoteDirect Link to This Post
Welcome to the Forum!

With a car that has been sitting for ten years you always worry about what the fuel has been doing...inside the gas tank...in the injectors. From your description it sounds as though the cold start injector is doing nothing, and the other injectors are unhappy. Is the 'start gas' you refer to spray-can either?

[This message has been edited by Gall757 (edited 09-12-2011).]

IP: Logged
Andreeas
Member
Posts: 65
From: Huskvarna, Sweden
Registered: Aug 2011


Feedback score: N/A
Leave feedback

Rate this member

Report this Post09-13-2011 01:24 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 start-gas is spray-can. I have removed the airfilter and "hose" and spray it where the hose was connected to the plenum air intake.

I understand what you say about the old petrol. I'm about to pour out both gas and oil and change filters. Is it something special I should look for in the gastank for example? Should i remove the injectors for a visual check?

IP: Logged
Basic88
Member
Posts: 78
From: Central,Florida,USA
Registered: May 2010


Feedback score: N/A
Leave feedback

Rate this member

Report this Post09-13-2011 02:02 AM Click Here to See the Profile for Basic88Send a Private Message to Basic88Edit/Delete MessageReply w/QuoteDirect Link to This Post
IF you are saying that you are trying to crank it with 10 year old fuel....even if it has been treated is not a good idea. Get that stuff out of there and put some clean fresh gas. Your fuel pressure is ok, what does that mean? I believe these things need like 16 to 20 lbs of pressure I may be out of line someone will correct me if so but make sure you check it with a gauge. If it was running fine 10 years ago and crapped out....there was a reason. All the things you said about getting new ignition parts sound good. 10 year old plug wires = no good. On the other hand it sounds like the thing is trying to come to life dispite all the bad elements and thats good! Im sure with some tinkering you can get it going. There are some smart people on this forum I couldnt keep my car on the road otherwise. IF you can get it started I would suggest Seafoam in the gas after all these years it will help clean up the fuel system . Good luck with your repair!

[This message has been edited by Basic88 (edited 09-13-2011).]

IP: Logged
phonedawgz
Member
Posts: 17011
From: Green Bay, WI USA
Registered: Dec 2009


Feedback score:    (23)
Leave feedback





Total ratings: 290
Rate this member

Report this Post09-13-2011 06:24 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
So when you add staring fluid the car runs. What does that mean?

First it means your ignition system is working

Next it means your fuel system isn't. Have you checked the fuel pressure? There is a schreader valve on the fuel rail for that purpose. Right after running the fuel pump prime (turn the key to on, and wait for two seconds) check to see how much pressure you have there. You can best do this with a gauge (Harbor Freight, fuel injection fuel pressure gauge $19.00), but you can get a rough estimate of the pressure by just depressing the valve and seeing how far the gas squirts up. It should easily squirt up and hit the rear deck lid. Less than that isn't enough fuel pressure to start the car.

Always have the appropriate fire extinguisher available when working on a fuel system.

If you do have the fuel pressure, the next thing is to check for a ECM ground signal at the injectors themselves.

[This message has been edited by phonedawgz (edited 04-25-2012).]

IP: Logged
Andreeas
Member
Posts: 65
From: Huskvarna, Sweden
Registered: Aug 2011


Feedback score: N/A
Leave feedback

Rate this member

Report this Post09-13-2011 03:54 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
Basic88: I don't really know how much fuel there was in the car when I got it, maybe about 10 litres or so, but when I got the car last year I filled it with some 10 litres more. So half of the fuel is REALLY old and half of it is about one year old. I do realize that even if it's ONLY one year thats not even good. So I will "get that stuff out" and get som new fresh gas (along with new oil and filters) as soon as I can!! ;-)

phonedawgz: I checked the fuel pressure with a gauge last year (when I got the car). I don't remember exactly but the pressure was somewhere around 40 psi. I looked in the Hayes-manual and found out that the pressure was allright.

"ECM ground signal at the injectors themselves"? Exactly what do you mean? And how can I check this?

I have checked that the injector to cylinder 5 ( i think... the one to the left on the "backside" of engine) has 12V. It has on both contacts. I also can hear how all of the three injectors on the backside (1,3,5) are ticking when I crank the engine. I have NOT checked whether the voltage gets down to around 7 volts when I crank... ( I read somewhere that it should go from 12 - 7 volts when the ECM sends signal to injectors?)

When I started troubleshooting I suspected something was wrong with the fuelsupply. The only thing that (now) made me wonder if it really was fuel-related was that the engine fires up for some 5 seconds without start-gas...
IP: Logged
phonedawgz
Member
Posts: 17011
From: Green Bay, WI USA
Registered: Dec 2009


Feedback score:    (23)
Leave feedback





Total ratings: 290
Rate this member

Report this Post09-13-2011 04:25 PM 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
My knee jerk guess would have been from the start that the injectors are stuck shut.

If the voltage reading on the ECM side if the injectors is several volts less than the +12v side of the injectors during cranking that would indicate the ECM is trying to fire them. You do have to make both readings during cranking so you can actually tell what is happening to the injectors.

The next thing I would do is pull the upper intake manifold, and then pull the fuel rail and the injectors. Using a voltage source test each injector to make sure it clicks, and to make sure you can get some flow through the injectors. This can be done via powering the fuel pump and seeing the spray from the injectors when they are powered (kinda dangerous), or by just using a 9v battery and some test leads and blowing through the injectors. Injector cleaner works to unstick the injectors. Finally you might want to do a test to see the spray pattern of the injectors, but a bad spray pattern would not be enough to keep the engine from starting.

While you have the injectors out - sometimes the injectors can be unstuck by just giving them a good rap with a screwdriver handle.

You need to replace the injector o-rings when you reassemble the engine. The fuel at the fuel rail is 40 psi. You don't want that to be leaking.

re: 5 seconds - the Fiero has a 7th injector - the cold start injector - that just squirts gas into the intake during cranking when the engine is cold. It only gets voltage when cranking. It is also controlled by a thermostatic switch, and that thermostatic switch has a small heater on it that gets heated during cranking. So the cold start injector will only squirt gas during the first attempts at cranking. After a while the heater has warmed up the switch and it stops squirting in the cold start gas

[This message has been edited by phonedawgz (edited 09-13-2011).]

IP: Logged
Andreeas
Member
Posts: 65
From: Huskvarna, Sweden
Registered: Aug 2011


Feedback score: N/A
Leave feedback

Rate this member

Report this Post09-14-2011 03:42 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
Just curios.. Arter cranking several times for a total of approx 20 - 30 secs - is it possible that the cold start injector has injected enough fuel to run the engine for those 5 secs??
IP: Logged
Gall757
Member
Posts: 10738
From: Holland, MI
Registered: Jun 2010


Feedback score: N/A
Leave feedback





Total ratings: 89
Rate this member

Report this Post09-14-2011 09:51 AM Click Here to See the Profile for Gall757Send a Private Message to Gall757Edit/Delete MessageReply w/QuoteDirect Link to This Post
If you have one or two injectors that are barely leaking gas the engine would probably fire after 30 seconds. I think the cold start injector is not functioning at all....do you know where that is? Just to the right of the distributor, there is a metal tube that goes into the fuel rail.
IP: Logged
Andreeas
Member
Posts: 65
From: Huskvarna, Sweden
Registered: Aug 2011


Feedback score: N/A
Leave feedback

Rate this member

Report this Post09-14-2011 10:00 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 think i know where its located (or I'll look in my Haynes manual). Is there some way to test its function??

[This message has been edited by Andreeas (edited 09-14-2011).]

IP: Logged
Andreeas
Member
Posts: 65
From: Huskvarna, Sweden
Registered: Aug 2011


Feedback score: N/A
Leave feedback

Rate this member

Report this Post10-09-2011 02:28 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
Haven't had so much time for the Fiero - but now I've recieved some new stuff from Fierostore. I ordered som ingitionparts like new sparkplugss and cables, cap, rotor, coil, ICM (just in case) air/fuel/oil-filter.
My plan is to pour out all gas and oil and replace with new along with the new filters. I will also change all the sparkplugs and cables to them, replace cap and rotor and coil. After that my plan is to check again that fuelpressure at the intake is ok, if it is I will check some of the rear injectors for voltage and if they are functioning (squirting gas).

Although I have a question. I find that the engine cranks really slow - can this be a part of the problem (that it wont start)? Do you have any ideas what to check to see why it's cranking slow?

I also still wonder if theres some way to the how/if the coldstart injector is working all right.

And..... IF I choose to change the ICM - do I have to remove the distributor to replace the ICM?

------------------
/Andreéas

IP: Logged
PFF
System Bot
Andreeas
Member
Posts: 65
From: Huskvarna, Sweden
Registered: Aug 2011


Feedback score: N/A
Leave feedback

Rate this member

Report this Post10-09-2011 02:31 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

Andreeas

65 posts
Member since Aug 2011
Is there a smooth way to get the old fuel out of the tank? Something special to think about (except having a fire extinguisher...) ???
IP: Logged
Gall757
Member
Posts: 10738
From: Holland, MI
Registered: Jun 2010


Feedback score: N/A
Leave feedback





Total ratings: 89
Rate this member

Report this Post10-09-2011 05:52 PM Click Here to See the Profile for Gall757Send a Private Message to Gall757Edit/Delete MessageReply w/QuoteDirect Link to This Post
No, the ICM comes out with 2 little screws.....don't loose them..and the distributor stays. Remove the distributor cap, however.

As for slow cranking, there are lots of reasons, but low voltage would be the first check....The alternator may not be charging after all this time.
IP: Logged
Andreeas
Member
Posts: 65
From: Huskvarna, Sweden
Registered: Aug 2011


Feedback score: N/A
Leave feedback

Rate this member

Report this Post10-11-2011 03:21 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
The battery is new and for some times now and then I "maintenance-charge" it. (hmm.. maybe not the correct word, but you hopefully know what I mean).

Since the motor isn't running at all it won't be the alternators fault.

Maybe it can be the fact that the car haven't been running for eleven years?

OR maybe its low voltage as you say caused by bad grounding or something???
IP: Logged
Gall757
Member
Posts: 10738
From: Holland, MI
Registered: Jun 2010


Feedback score: N/A
Leave feedback





Total ratings: 89
Rate this member

Report this Post10-11-2011 09:37 PM Click Here to See the Profile for Gall757Send a Private Message to Gall757Edit/Delete MessageReply w/QuoteDirect Link to This Post
You would have to assume that the main electrical connections have corroded over that time span. Do you have any WD-40?....electrical connections like that stuff.
IP: Logged
Andreeas
Member
Posts: 65
From: Huskvarna, Sweden
Registered: Aug 2011


Feedback score: N/A
Leave feedback

Rate this member

Report this Post10-26-2011 12:57 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
Ok, I havent done my homework yet, cause I have not had the time (change oil/fuel) but I just wanted to check the fuelpressure again...

I´ve got about 60 psi right before the fuelrail (i think its called the shreader valve).

Isnt this way too much? Can this cause problems?

The fun thing about today was that I turned the key and after maybe 5 seconds the enginge fired up and ran for about 10 - 15 seconds.


I´ve tried to search for a smooth way to get the old fuel out of the tank, but I cant find... Any ideas?
IP: Logged
phonedawgz
Member
Posts: 17011
From: Green Bay, WI USA
Registered: Dec 2009


Feedback score:    (23)
Leave feedback





Total ratings: 290
Rate this member

Report this Post10-26-2011 02:41 PM 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
 
quote
Originally posted by Andreeas:

Just curios.. Arter cranking several times for a total of approx 20 - 30 secs - is it possible that the cold start injector has injected enough fuel to run the engine for those 5 secs??


Yes
IP: Logged
phonedawgz
Member
Posts: 17011
From: Green Bay, WI USA
Registered: Dec 2009


Feedback score:    (23)
Leave feedback





Total ratings: 290
Rate this member

Report this Post10-26-2011 02:45 PM 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

phonedawgz

17011 posts
Member since Dec 2009
 
quote
Originally posted by Andreeas:

Is there a smooth way to get the old fuel out of the tank? Something special to think about (except having a fire extinguisher...) ???


If you fuel pressure gauge has a line on it - take the line off of the gauge. Now hook up the line to the test valve on the engine, and put the other end of the line into a bucket.

Then jump the fuel pump relay to make the pump run continuously. The fuel pump relay is located on the firewall, behind the drivers seat, in the engine compartment. There are most likely two relays there. The fuel pump relay has wires that are:

Orange/Black
Tan/White
Green/White
Black

To make the pump run, take the relay out of the socket and jump the Orange/Black wire to the Tan/White wire with a paperclip. The fuel pump will then run (key on or off)
IP: Logged
Andreeas
Member
Posts: 65
From: Huskvarna, Sweden
Registered: Aug 2011


Feedback score: N/A
Leave feedback

Rate this member

Report this Post10-26-2011 02:45 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
Phonedawgz:

Got your reply.... the thing is that today it fired up after 2-3 secs of cranking.. had it running for aprox 10-15 secs.. then i tried give it some more gas (with pedal) and it died out on me.

What about the high fuelpressure... it's way to high... but maybe its not a problem?
IP: Logged
phonedawgz
Member
Posts: 17011
From: Green Bay, WI USA
Registered: Dec 2009


Feedback score:    (23)
Leave feedback





Total ratings: 290
Rate this member

Report this Post10-26-2011 02:47 PM 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
It is too high but the engine should run.

You are not getting a problem of too much fuel right?

also I doubt the fuel is so bad that it isn't running.

I still think your injectors are just stuck shut from sitting with gas in them.
IP: Logged
phonedawgz
Member
Posts: 17011
From: Green Bay, WI USA
Registered: Dec 2009


Feedback score:    (23)
Leave feedback





Total ratings: 290
Rate this member

Report this Post10-26-2011 02:50 PM 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

phonedawgz

17011 posts
Member since Dec 2009
I assume your service engine soon light comes on when you turn the key to on.

If your SES light is not coming on, and the fuel pump doesn't run for two seconds when you first turn the key to on, your problem may very well be the ECM isn't getting power. If this is the condition, the engine will still start on the cold start injector after a bit of cranking and then run for a few seconds.

If either the SES light is coming on, or the fuel pump runs for two seconds after turning the key to start (but not cranking) then your ECM is running.
IP: Logged
PFF
System Bot
Andreeas
Member
Posts: 65
From: Huskvarna, Sweden
Registered: Aug 2011


Feedback score: N/A
Leave feedback

Rate this member

Report this Post10-26-2011 02:51 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
Smart thinking about using the fuelpump relay and the gauge line.. Thanks for the tip....
IP: Logged
Andreeas
Member
Posts: 65
From: Huskvarna, Sweden
Registered: Aug 2011


Feedback score: N/A
Leave feedback

Rate this member

Report this Post10-26-2011 02:54 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

Andreeas

65 posts
Member since Aug 2011
My SES-light seems to work, but I read another thread and Al Haley wrote that if the engine doesnt run for 40-45 sec then you cant rely on what the computer says, but I havent got it verified...
For the moment I'm reading the GM manual on the net.
IP: Logged
Gall757
Member
Posts: 10738
From: Holland, MI
Registered: Jun 2010


Feedback score: N/A
Leave feedback





Total ratings: 89
Rate this member

Report this Post10-26-2011 04:28 PM Click Here to See the Profile for Gall757Send a Private Message to Gall757Edit/Delete MessageReply w/QuoteDirect Link to This Post
It's not so much about time than it is about temperature. When the car gets over a temperature threshold, the computer responds in what is called 'closed loop' operation....sampling data and such.... your car has not hit that temperature yet....somewhere around 190* F.
IP: Logged
Andreeas
Member
Posts: 65
From: Huskvarna, Sweden
Registered: Aug 2011


Feedback score: N/A
Leave feedback

Rate this member

Report this Post10-26-2011 04:45 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
Hmmm.. Thats a problem. Bet it will have to run for some minute to get that temp..
IP: Logged
phonedawgz
Member
Posts: 17011
From: Green Bay, WI USA
Registered: Dec 2009


Feedback score:    (23)
Leave feedback





Total ratings: 290
Rate this member

Report this Post10-26-2011 06:05 PM 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
The computer will run anytime the key is on, engine running or not, engine warm or not.

You can connect a scanner and see the throttle, the temps ect with the key on, engine off.

The computer is not going to tell you anything about what is happening.



Backprobe the Pink/White wire of the injector connector and measure the voltage when you crank the engine.



You should get about 10-12v

Then back probe the Green/Black wire of the same connector and crank the engine. You should have about +12 key on before cranking. During cranking you should get about 4v less than what you got on the Pink/White wire.

If you get 4v less on the second test that means the ECM is trying to fire the injectors and they aren't injecting gas

If you get the same voltage on the Pink/White as you do on the Green/Black that means the ECM is NOT trying to fire the injectors.

[This message has been edited by phonedawgz (edited 10-26-2011).]

IP: Logged
Andreeas
Member
Posts: 65
From: Huskvarna, Sweden
Registered: Aug 2011


Feedback score: N/A
Leave feedback

Rate this member

Report this Post04-22-2012 02:37 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
Ok, now I have done my homework. The engine fires up and I've had it running for about 45 secs by pumping the gaspedal. If I dont touch the pedal it will die after some 5 secs.

I'm getting errorcodes 34 and 42. This should be the MAP-sensor and some problem with the ICM. I changed the ICM before I had it running so its a new one from Fierostore.

I've searched the forum for troubleshooting the MAP but I can't find anything. Can some tell me what to do or link som thread about this? Should I troubleshoot the MAP first and then the ICM? Could these problems be related?
IP: Logged
Pete Matos
Member
Posts: 2291
From: Port St. Lucie, Florida
Registered: Jan 2010


Feedback score: (2)
Leave feedback

Rate this member

Report this Post04-22-2012 03:07 PM Click Here to See the Profile for Pete MatosSend a Private Message to Pete MatosEdit/Delete MessageReply w/QuoteDirect Link to This Post
Hey Phonedawgs... Just thought I would drop in here and say YOU ARE THE MAN!!! I just love how you try to help everyone no matter what they know or do not know and you really seem to know your stuff. Well done man. Peace


Pete

IP: Logged
phonedawgz
Member
Posts: 17011
From: Green Bay, WI USA
Registered: Dec 2009


Feedback score:    (23)
Leave feedback





Total ratings: 290
Rate this member

Report this Post04-22-2012 03:47 PM 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
Thanks Pete

Anyways - Try electrically unplugging the MAP sensor. This will take the MAP input out of the ECM's formula to figure out how much fuel to inject. If that makes the car run much better - then check the vacuum line to the MAP sensor. If the vacuum line is not working properly, the MAP sensor can be telling the ECM that the throttle is fully open and then the ECM will be dumping huge amounts of fuel into the engine.
IP: Logged
Andreeas
Member
Posts: 65
From: Huskvarna, Sweden
Registered: Aug 2011


Feedback score: N/A
Leave feedback

Rate this member

Report this Post04-24-2012 03:13 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
I tried electrically unplugging the MAP-sensor. the engine acts the same - found no change. As long as your pumping with the gas-pedal you can hold it running. As soon as you stop "pumping" the pedal it will die...
Should I check the vacuum line anyway? In that case - how do I check it?
IP: Logged
Andreeas
Member
Posts: 65
From: Huskvarna, Sweden
Registered: Aug 2011


Feedback score: N/A
Leave feedback

Rate this member

Report this Post04-24-2012 03:18 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

Andreeas

65 posts
Member since Aug 2011
Or can anyone tell me how to check if the MAP-sensor is working as it should?
IP: Logged
PFF
System Bot
Andreeas
Member
Posts: 65
From: Huskvarna, Sweden
Registered: Aug 2011


Feedback score: N/A
Leave feedback

Rate this member

Report this Post04-25-2012 02:30 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
After a tip from a friend I tested the TPS. It measures 0,75 V when its closed and 4,49 when its fully opened. Is this ok?

Just to make clear. If I dont touch the gaspedal the engine dies after about 2-3 secs now. My friend had it running for about 45 when he was pumping with the pedal. Its fluttering between 500 and 2000 rpm. As soon as he stops pumping with the pedal, the engine dies.

Since I've got errorcode 34 I took out the 3-pin contact from the MAP-sensor. It didnt make any difference at all, nor in diagnostic mode or in "normal" mode. those 3 pin looks like crap! curved and crooked. Could this be the problem, maybe? I tried holding/pushing the contact into the map-sensor when my friend turned the engine on but it didnt make any difference.

I've got some tips to check for vacuum leaks etc, but I havent got any comments about HOW to check it. I've read in the Haynes-manual and I've tried to search this forum, but I just can't find anything.

Someone who has a clue what the problem could be? Or can tell me how to check the function of vacuum / MAP??
IP: Logged
Gall757
Member
Posts: 10738
From: Holland, MI
Registered: Jun 2010


Feedback score: N/A
Leave feedback





Total ratings: 89
Rate this member

Report this Post04-25-2012 06:24 PM Click Here to See the Profile for Gall757Send a Private Message to Gall757Edit/Delete MessageReply w/QuoteDirect Link to This Post
The symptom for a vacuum leak is usually a high idle....and you don't have that problem. A bad connector seems more likely, or possibly a broken wire in the harness. MAP sensors don't often fail, so checking the wiring would be good. Phonedawgz should show up pretty soon with the real answer.
IP: Logged
Andreeas
Member
Posts: 65
From: Huskvarna, Sweden
Registered: Aug 2011


Feedback score: N/A
Leave feedback

Rate this member

Report this Post04-27-2012 03:09 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
Thats right.. high idle isnt really my problem... i dont even know if the idle itself is the problem. It just idles for some seconds and then dies. Even if I pump with the gaspedal its hard to get it going. The rpm "flickers" . Its impossible to have it steady in rpms. thats why I think its something with air/fuel-combination...

The 3-pin-connector to the map looks like crap ...the pins are bent and curved.. could this be a problem? I'd like to think so, but I've read that the engine would run even without the map (i.e. limp-home, when you shortcut A and B).

IP: Logged
Gall757
Member
Posts: 10738
From: Holland, MI
Registered: Jun 2010


Feedback score: N/A
Leave feedback





Total ratings: 89
Rate this member

Report this Post04-27-2012 09:58 AM Click Here to See the Profile for Gall757Send a Private Message to Gall757Edit/Delete MessageReply w/QuoteDirect Link to This Post
The TPS numbers are OK....

Have you tested the pickup coil and the ICM? I don't think fuel delivery is your problem, although you could spray some starter fluid in there and see if it smooths out. The problem seems more electrical in nature.
IP: Logged
Andreeas
Member
Posts: 65
From: Huskvarna, Sweden
Registered: Aug 2011


Feedback score: N/A
Leave feedback

Rate this member

Report this Post04-27-2012 04:18 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
I did try starting it with startgas (spraycan) today. It did run better/longer. . As long as I sprayed start-gas I could hold it running without problem. I started it up in "normal-mode". had it running for approx 30 sec twice... After that I checked the errorcodes again. Still 34 and 42.

My own conclusion of this is some kind of fuel-related problem?? (or air-related)

I've got the tip to spray som startgas around the vacuumhoses to check if the rpm's increase. That would indicate vacuumhose-leakingproblem. Didn't have the time to check this today. Do you think its possible the problem is vacuumleak?

Haven't tested the pickup-coil or ICM.. Why? The pickup-coil was changed for about two or three years ago by the owner before during his attempt to get it running. The ICM i just replaced 2 weeks ago when I also changed filters/ignition-cables and so on...
But for sure - they could be broken... But the fact that it runs pretty ok with starter-gas says me that the pickup-coil and ICM must be working fine?
IP: Logged
weloveour86se
Member
Posts: 4289
From: maine
Registered: Feb 2011


Feedback score:    (115)
Leave feedback





Total ratings: 75
Rate this member

Report this Post04-28-2012 12:21 AM Click Here to See the Profile for weloveour86seSend a Private Message to weloveour86seEdit/Delete MessageReply w/QuoteDirect Link to This Post
 
quote
Originally posted by Andreeas:

I did try starting it with startgas (spraycan) today. It did run better/longer. . As long as I sprayed start-gas I could hold it running without problem. I started it up in "normal-mode". had it running for approx 30 sec twice... After that I checked the errorcodes again. Still 34 and 42.



Stop trying to run the car on ether. Starter fluid, startgas, what ever you would like to call it. Over use starter fluid and you'll wreck your motor. Don't use any more then a 3 second count shot of it. Your trying to run an unknown engine on NOS by doing so basically.

Edit. Does the tachometor bounces or move at all when you try to start it? Does you check engine soon light work? Please take it easy with the starter fluid. It can destroy a motor.

[This message has been edited by weloveour86se (edited 04-28-2012).]

IP: Logged
Andreeas
Member
Posts: 65
From: Huskvarna, Sweden
Registered: Aug 2011


Feedback score: N/A
Leave feedback

Rate this member

Report this Post04-29-2012 02:47 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
The tachmeter bounces/moves when I start the engine. It moves to around 2-300 when I crank. When the engine fires up it moves to around 1500-2000. when I used startgas it did show about 2000 rpms...'

The SES-light works fine I think. When I put it into diagnostic mode it gives me first 12 then 34 then 42.

It think that when I crank in diagnostic-mode the SES flickers a lot. Is this good/bad? If it is not good, I'll check this again (just so it just not another Fiero-nightmare :-) )

Have anyone had a ticking noise from around the IAC/TPS when in diagnostic-mode? When the car is in diagnostic-mode (limp-home) ang I turn the key to ON, I hear some ticking from somewhere around the throttle. When I try to start the car, the engine runs for some secs then dies. The ticking noise continues until I turn key to OFF. Is this normal?

Thanks for the information about startergas...

------------------
/Andreéas

IP: Logged
Gall757
Member
Posts: 10738
From: Holland, MI
Registered: Jun 2010


Feedback score: N/A
Leave feedback





Total ratings: 89
Rate this member

Report this Post04-29-2012 03:05 PM Click Here to See the Profile for Gall757Send a Private Message to Gall757Edit/Delete MessageReply w/QuoteDirect Link to This Post
It is beginning to look like 2 problems..

1. If the starter fluid makes the engine run better, you have a problem with the injectors...probably stuck. Not all of them, but enough to kill the engine. That is probably from sitting for so long.

2. If the engine does run with starting fluid, but at 2000 rpm, you probably have a vacuum leak, but you can't fix that until you get the engine to run....

There are threads on here about getting the injectors out and un-stuck.....

edit: I don't know about the SES light flickering,,, but it does not seem right.

[This message has been edited by Gall757 (edited 04-29-2012).]

IP: Logged
Andreeas
Member
Posts: 65
From: Huskvarna, Sweden
Registered: Aug 2011


Feedback score: N/A
Leave feedback

Rate this member

Report this Post04-29-2012 04:16 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 vad the injectors out of the engine. Tested them with à battery. Electrically they seem to work properly. But I didnt test the "injectorfunction" with liquid or gas.. I wonder if I should have them out again and "hit" them with a screwdriver or something. Maybe I should let them be functiontested?...
If I'm about to get new ones.. Where do i get info about specifications of the injectors?
IP: Logged
Previous Page | Next Page

This topic is 2 pages long:  1   2 
next newest topic | next oldest topic

All times are ET (US)

Post New Topic  Post A Reply
Hop to:

Contact Us | Back To Main Page

Advertizing on PFF | Fiero Parts Vendors
PFF Merchandise | Fiero Gallery | Ogre's Cave
Real-Time Chat | Fiero Related Auctions on eBay



Copyright (c) 1999, C. Pennock