Help! 84 Corvette warm start

[Tom1]

When car is cold it starts and drives ok, but when it is parked and restarted a little later (say 1 hour) it will crank but has no power and wants to die. After I let it set until it cools down it will start and drive ok again until I park it and restart it later while it is still warm. Fan works normally and engine does not overheat while driving. Could this be caused by a faulty EGR solenoid? The EGR valve seems to be working ok. I intend to check for codes tomorrow if time allows. Any comments from anyone with similar experience will be appreciated.

 

[Robertwav1]

When car is cold it starts and drives ok, but when it is parked and restarted a little later (say 1 hour) it will crank but has no power and wants to die. After I let it set until it cools down it will start and drive ok again until I park it and restart it later while it is still warm. Fan works normally and engine does not overheat while driving. Could this be caused by a faulty EGR solenoid? The EGR valve seems to be working ok. I intend to check for codes tomorrow if time allows. Any comments from anyone with similar experience will be appreciated.

Fuel pressure regulator maybe. Check vacuum lines for either traces of fuel or strong fuel order, a sure sign of a leaking diaphragm. Easy check to start with.

 

[Hot Rod Roy]

Fuel pressure regulator maybe. Check vacuum lines for either traces of fuel or strong fuel order, a sure sign of a leaking diaphragm. Easy check to start with.

Robert, are you knowledgeable on the '84 Cross-Fire injection system? It's a bit different than your '93 (like, 100% different). No vacuum line to the fuel pressure regulator.

Tom, take a look at your injectors after you shut off the engine. They shouldn't drip fuel after engine shut down.

 

[Robertwav1]

Robert, are you knowledgeable on the '84 Cross-Fire injection system? It's a bit different than your '93 (like, 100% different). No vacuum line to the fuel pressure regulator.

Tom, take a look at your injectors after you shut off the engine. They shouldn't drip fuel after engine shut down.

No, I'm not familiar with the cross fire injection however, my car acted that way and it wasn't the injectors. From what I understand the fuel pressure regulator adjusts intervals during which fuel injectors open and if this is not correct flooding can occur. The question asked was if anyone had a similar experience?

 

[Tom1]

84 Corvette Warm Start

Just want to thank everyone for their suggestions so far. I have purchased the TBI service kit (new gaskets, etc.) because I just wanted to see what was inside these units and make sure they were as they should be since I bought the car used with several thousand miles. Anyway during this process I noticed that the fuel regulator on the rear TBI unit (drivers side) has a small threaded bolt which is used to adjust the position of the spring. Well since I did not know exactly what I was doing I accidently turned this adjustment bolt and now don't know where to reset it. The instructions that came with the rebuild kit says this is set at the factory and not to mess with it. Does anyone know what I am talking about and how I can reset this adjustment? If so I would be most appreciative for any help.

 

[Tom1]

Just want to thank everyone for their suggestions so far. I have purchased the TBI service kit (new gaskets, etc.) because I just wanted to see what was inside these units and make sure they were as they should be since I bought the car used with several thousand miles. Anyway during this process I noticed that the fuel regulator on the rear TBI unit (drivers side) has a small threaded bolt which is used to adjust the position of the spring. Well since I did not know exactly what I was doing I accidently turned this adjustment bolt and now don't know where to reset it. The instructions that came with the rebuild kit says this is set at the factory and not to mess with it. Does anyone know what I am talking about and how I can reset this adjustment? If so I would be most appreciative for any help.[/QU

Come on you Crossfire fans! I'm sure someone out there has rebuilt these TBI units. These regulators are real simple inside there are only four parts, diaphragm, adjustment screw or bolt, a cone shaped cup and a large spring. All the shop manuals I have say not to take them apart because of the large spring pressure and you could get hurt if the spring jumps out, but I did not find this a problem. I was careful removing the screws - four in total - and I left two screws on opposite corners to be removed last. I was able to keep the spring compressed easily with one hand. The rebuild kit contains new diaphragms and the only way you can replace them is to take the thing apart which the manuals say not to do. I guess they want you to take them to the dealer so they can charge you big bucks. I will admit I made a mistake by not noting the location of the cone shaped cup on the threaded bolt. I hope someone else who has taken one of these apart can remember about how far the metal tab on the cone shaped cup was located from the end of the opening on the side of the spring cover. If my memory serves me correctly I am thinking maybe 1/8 of an inch. Thanks for any assistance.

 

[Antz81]

Unfortunately I don't know the answer to your question (I checked in a manual i have and it just said it's serviced as a complete unit). But give it a few days as not everyone checks in daily.
After a few days if I haven't seen an answer I'll post a link in the C3 section to try pick up any 82 owners that don't check the C4 section.