3.1 runs when cold then dies, won't restart

[AzMedic25]

Hi, I have read all the previous posts I could get from a search but I have to ask. Girlfriends 1991 Lumina Euro 3.1L started having problems some time back with surging and loosing power when climbing hills, replaced the fuel filter which helped. Now I have had the problem of starting fine when cold but after warming up, dies like a switch had been turned off. I had replaced the fuel pressure regulator when I noticed pools of gas in the air inlet from the filter prior to the current problem. It had gas coming out the vacuum port. Fuel rail pressure reading 40-46 psi.
Soon after changing the fuel regulator, while driving to work, the car died and would not start. Towed it home and next morning started right up. It stalled and wouldn't start after about 3 miles. I have changed out the crank position sensor, then tested the ICM and coils with both showing normal. Last night I fired it up and watched the gauges with the engine shutting down after temp gauge started rising.
Any suggestions as to what could be causing the problem would be appreciated.

[maxwedge]

Welcome to AF, Basics, when it won't start do you have spark? Will it start spraying carb cleaner into the intake?

[danielsatur]

Bad catalytic converters can choke an engine out!

[Tony Silva]

Fuel pump possibly....man these wierd run and then no run situations are the worst to narrow down. I'd take a stab at sayin' the fuel pump is going bad.

Check into it...once it dies out...try to keep it running with spraying some starting fluid inside the throttle body. if it runs with the starting fluid then your prob is with fuel delivery.

[danielsatur]

What do you need for Horse power?
Air, Fuel, Ignition Timing, and Exhaust.

Air - Air filter, MAF, IAT sensors, or unmetered air leaks on PCV, EGR, and Air Intake system.
Ign - bad coil, COP's, or spark plug wires when hot.
Fuel - bad fuel filter, fuel pressure, fuel pump relay, fuse, or pump.
Exhaust - Plugged catalytic converter, or exhuast system

[AzMedic25]

No Catalytic Converter on this car, girlfriend bought it and found out later that PO had taken it off.

[AzMedic25]

Originally Posted by maxwedge

Welcome to AF, Basics, when it won't start do you have spark? Will it start spraying carb cleaner into the intake?

Spark is there after it stalls and did start after the first time it did it but has not since. Once it stalls, have to wait till it cools off to start and run again.

[AzMedic25]

Originally Posted by Tony Silva

Fuel pump possibly....man these wierd run and then no run situations are the worst to narrow down. I'd take a stab at sayin' the fuel pump is going bad.

Check into it...once it dies out...try to keep it running with spraying some starting fluid inside the throttle body. if it runs with the starting fluid then your prob is with fuel delivery.

I had a fuel injector pressure tester on it after it stalled and it showed 40psi while cranking. It will not start with starting fluid or carb cleaner. It did the first time it stalled but has not since. Once it stops running, I have to wait for it to get cold to start again.

[AzMedic25]

Originally Posted by danielsatur

What do you need for Horse power?
Air, Fuel, Ignition Timing, and Exhaust.

Air - Air filter, MAF, IAT sensors, or unmetered air leaks on PCV, EGR, and Air Intake system.
Ign - bad coil, COP's, or spark plug wires when hot.
Fuel - bad fuel filter, fuel pressure, fuel pump relay, fuse, or pump.
Exhaust - Plugged catalytic converter, or exhuast system

Air - Has K&N filter just serviced 2 days before troubles started. Any suggestions on testing MAF sensor?? PVC was replaced when Fuel Rail Regulator was replaced.
Ignition - Tested coils and Ignition Module at AZ and spark plugs and wires have less than 5000 miles on them.
Fuel - Runs fine till it starts warming up, can hear fuel pump and has 40psi on fuel injector pressure tester. Fuel filter had been changed about 2000 miles ago.
Exhaust - PO removed Cat (for whatever reason I don't know).

Cleaned EGR valve this morning along with IAC module but no change.


Also, forgot to mention, when checking codes only flashing 12.

[maxwedge]

You are probably loosing cranking rpm signal to the pcm, or the pcm is bad as they were problematic, try tapping the pcm frimly with a lite hammer handle see if it kicks, the ign module was also common on this car. A full scan would show if it had cranking rpms when it wouldn't start.

[AzMedic25]

Originally Posted by maxwedge

You are probably loosing cranking rpm signal to the pcm, or the pcm is bad as they were problematic, try tapping the pcm frimly with a lite hammer handle see if it kicks, the ign module was also common on this car. A full scan would show if it had cranking rpms when it wouldn't start.

So.... I think I got it figured out.... went out to tap on the PCM as suggested by Maxwedge... Also had read elsewhere on testing injectors for voltage and ohms.
Well, while the 2 accessible injectors were unplugged from the wiring harness, injector #1 and injector #6, it started up when warm!!!! Plugged in the injector #1, it started up and ran... plugged in injector #6, DEAD!!! Crank but no start. I guess #6 injector is the culprit.. Going to get new injector and see what happens.. Thanks to all whom have offered assistance, I will let all know the outcome when I finish...

[danielsatur]

A local diesel shop can fix, micro bath, and test the flow rate for $20.

[maxwedge]

Replace it.

[AzMedic25]

Well, changed out the injector and car is running like new. Thanks to all for the assistance!!! Now to go to work on the other car....

[jerryr12]

i had the problem with 3.1 and it was a ground in the injector by the oil cap unplug that injector
and the car runs no stalls plug the injector in car dies try it and see