Question: 88 Corvette Hard Start when hot, idles rough at stop

[SpeedyKev64]

Can someone help me with a couple of problems I am having with my 88 Corvette?

The engine starts fine when it is cold. However, when it is hot, it takes a two or three times of turning the ignition on and off to start it.

Also, when the car is idling at a stop while in drive, the engine misses. Usually, the tachometer will fluctuate from 500 to 600 to 700 rpm. In park position, the rpm will fluctuate between 700 and 800 rpm.

I would deeply appreciate any insight to my problems.

Thanks,

SpeedyKev64

 

[Schrade]

Welcome onto the boards there...

The hard hot restart COULD be leaky injectors. If you don't have a fuel pressure guage, go to a local shop, and get a static fuel pressure test, AND, get them to check leakdown time, for at least 10 minutes, if it does NOT drop. If it drops within 10 minutes, you probably have leaky injectors.

Don't let them sell you a fuel pump, without showing you that there's no leaks in the line, or the fuel pressure regulator, or the injectors.

Fuel pressure first - NOTHING else up front. Post results. YOU NEED 40+PSI.

 

[vigman]

Kevin Quick N dirty test

At night...... in a dark area pop the hood and look at the area where the plug wires go....
See a light show...?
Got bad wires..
So any history on this car?

Mike

 

[Hib Halverson]

While this issue is not quite as simple to solve as suggested above the combination of hard starting when the engine is hot/warm and rough or unstable idle can mean leaking injectors.

The fuel pressure test suggested above is the first step however, the statement that if you note pressure drop inside 10 min, you probably have leaking injectors is an oversimplification.

Leaking injectors is just one of several possibilities. Others are: leaking ball check in the fuel pump or faulty fuel pressure regulator.

The best bet is to get ahold of a fuel pressure tester for an EFI engine then run the fuel pressure tests listed in the Factory Service Manual. Those tests will help you identify the problem before you go buy injectors.