'91 stalls when warm - after restart
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'91 stalls when warm - after restart
I have a '91 with 70K miles. I recently had Ford injectors put in - new cap, rotor, plugs, O2 sensor, and spark plug wires. The car runs great. If I come back from a run and restart it after 10 minutes or so - it starts and dies. Restart a few times it starts and stalls. If I catch it right and rev the engine it will stay running - idles low but okay. I don't have a fuel pressure gauge but I know after I got the injectors done that the pressure was in the upper 30's.
Any thoughts? Should I ignore it? Doesn't the ECM keep a car idling? Could it be a leaky injector and I'm burning off fuel? I'm limited to what I can check - the fuel pressure gauge looks like it would be a tight fit on the rail. Do I have to remore the module in front of it?
Thanks!
Any thoughts? Should I ignore it? Doesn't the ECM keep a car idling? Could it be a leaky injector and I'm burning off fuel? I'm limited to what I can check - the fuel pressure gauge looks like it would be a tight fit on the rail. Do I have to remore the module in front of it?
Thanks!
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Have you had your ICM (ignition control module) tested? They will check them for free at NAPA or AutoZone. It could be going ****-up on you like mine did.
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latest news on '91 stalls when warm
Took the car to the Vette Shop. So far they have found out the EGR is bad. I'll search some posts to check on this. I thought the EGR was during warm up only. Maybe I'm getting a vacuum leak from it?
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If the egr valve is sticking when its warmed,it can allow too much egr to enter the engine and cause stalling.
Be sure to check the vacuum lines going to it,they break and brittle.
If a sensor(Map) is in the way to do an FP test,remove it out of the way to access the valve.
Its tough to say whats wrong though,Ive seen egr get misdiagnosed many times for stalling,running problems.Was there a code?
Let us know whassup.
Be sure to check the vacuum lines going to it,they break and brittle.
If a sensor(Map) is in the way to do an FP test,remove it out of the way to access the valve.
Its tough to say whats wrong though,Ive seen egr get misdiagnosed many times for stalling,running problems.Was there a code?
Let us know whassup.
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Be sure and check the EGR diaphragm, too. If it's cracked and no longer able to hold vacuum, that can certainly cause the problem you're experiencing, too.
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Well the latest is not good news. The Vette shop has had the car for almost two weeks. They called today and said the fuel pressure sending unit was bad. The parts would be $100 for something? and $700 for a new fuel pump because you can't buy just the sending unit.
Initially I said let me fix it - I thought there was a good post on fixing these sending units. The shop explained they had the pump out of the car and the sending unit was cracked. I'm waiting now for a huge repair bill. I hope it's fixed.
Initially I said let me fix it - I thought there was a good post on fixing these sending units. The shop explained they had the pump out of the car and the sending unit was cracked. I'm waiting now for a huge repair bill. I hope it's fixed.
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Hmmm, the sending unit controls the gage and the pump is a separate item - but I'd guess the shop is telling you that something about the entire assembly is broken. You can't fix that (well you might try a little JB Weld, but a shop isn't going to warranty that type of repair). Price I guess is ok - the last time a looked - and that was a couple of years ago - the sender was $300 or so, the pump about $80.
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I got the car back - $1,100. They showed me the bad part. SunCr - your correct, the gas gauge and pressure gauge are separate. The write-up I saw on the forum was to rebuild the the gas gauge assy. The cracked part on my car was the pressure unit at the top plate of the assy.
Took the car for a hard run. It is running better. It restarted and didn't stall after it was warm. The idle was smoother - the car felt like it was idling on its own, not idling poorly and having the computer kick in to keep it going. Went for a third cruise same day and it idled a little rough at the start but smoothed out once it got going. I think the mechanic got it right - I hope so. Have put many $'s into the L98 at this point between intake gaskets, injectors, and the fuel pump I just did. See you on the road!
Took the car for a hard run. It is running better. It restarted and didn't stall after it was warm. The idle was smoother - the car felt like it was idling on its own, not idling poorly and having the computer kick in to keep it going. Went for a third cruise same day and it idled a little rough at the start but smoothed out once it got going. I think the mechanic got it right - I hope so. Have put many $'s into the L98 at this point between intake gaskets, injectors, and the fuel pump I just did. See you on the road!
