1993 lumina van 3.8 stalling problem.

[Chadly]

1993 lumina van 3.8 stalling problem.

Hi,
Our van was stalling out while driving and then wouldn't start for a few minutes after stalling. The few minutes turned into 10, 15, 20 minutes over time. It seemed to start stalling after driving for awhile. We changed the ignition control module a week ago and so far it hasn't stalled out while driving but now sometimes won't start up after stopping(about once every 10-15 times we stop and shut it off). Say we run into a corner store for 5 minutes we come out and it won't start. We never have a problem starting it up in the morning or after it has sat for awhile (30 minutes or longer). We have taken it to an auto store and they ran a test which led us to replacing the ignition control module. We have had some suggestions from friends, family and ideas from our own research. We found this site and are looking for more suggestions before we invest more time and money into this.

Thank you all in advance for any help, it will be appreciated greatly.

[sysopt]

"Sometimes won't start" means a no start and no crank or cranks and no start?

[Chadly]

Sometimes won't start means crank and no start. Sorry I wasn't clearer on that. Thanks.

[Chadly]

Bump.

[Slammerz]

Sounds like the Fuel Pump - get a fuel pressure tester and test the pressure. I had a similar problem got so bad it would run for 2-3 minutes and then not start for 5-6 minutes (Sometimes hours). It seems that if the fuel pressure is low then the pressure regulator on the fuel rail never opens to let fuel back to the tank through the return fuel line. When this happens, air (or fuel vapor) can build up in the fuel rail, essentially causing vapor lock. If the pressure tests OK and it still won't start or it stalls use the pressure relief valve on the tester to bleed off some gas and see what happens. Another test would be to disconnect the return fuel line and see if gas is returning to the tank.

Sometime, when the car won’t start, and the key off bleed the fuel pressure. Then disconnect the return fuel line (There’s a quick connect under the car (drivers seat area) right near the fuel filter). Place the ends into a fuel container and have someone turn the key to ‘on’ position (this causes the fuel pump to run for 2 seconds) then off and on again you should see gas coming out of the return fuel line by the second or third cycle. If there is no fuel then it’s either the pump (fuel pressure too low) or the pressure regulator (Pressure normal or high)

[Mike.N]

Replace the gas cap or better yet pop of the little flter on the inside of the cap. I drilled a whole through mine. What maybe happening is the gas cap is plugged (fuel tank air vent) and the fuel pump is causing negative pressure in your fuel tank therefore starving the engine of fuel. Next time your vehicle quits, try oppening your fuel cap and listen as your tank returns to it's normal size. The negative vacuum will actualy suck in the tank until the vaccuum overtakes the draw of the pump. I hope this helps.

[troubleshooter]

You may also want to consider the vacuum system. My APV would stall while idling and then wouldn't start until the engine cooled off. I replaced the vacuum canister purge valve and so far I have had no more problems. Also consider the throttle position sensor and the idle air control valve.