duno if i missed the answer in my search of forum for hard warm start but searched for 3 days..

ok, starts right up cold, got to crank it a bit after engine warm and sitting for more than maybe 15 to 25 minutes .. not sure how long..

it starts right up if i give it a little gas pedal.. but just cranks for a a bit if I don't give it any gas...

hope its not leaking injector.. its an 87 convertible which otherwise runs very nicely ... smooth and steady for the most part, the occasional rumbley idle once in a while ... but I think that is carbon from driving around here in the city. once I get it highway borne and clean it out, it idles fine...

any clues would be appreciated much

thanks,
tk

 

Certainly looking that way. Only was to confirm is to ohm the injectors hot and cold and see what the readings are. Cranking with your foot on the pedal cuts off the injectors to clear a flooded engine which is what you would have if the injectors are leaking down

http://forums.corvetteforum.com/c4-t...e-is-warm.html

http://forums.corvetteforum.com/c4-t...after-hot.html

 

Make sure you hear the fuel pump priming for a couple seconds when you click the ignition to on when warm. My fuel pump relay went out and stopped working when it was hot. When that happens you have to crank until you get oil pressure, then that also allows the fuel pump to come on without the relay.

I still have the problem a little, and I tested it all out and it must be a leaking injector. You need a fuel pressure gauge to check that out. If you have one, hook it up and see how fast the pressure drops after you prime the system (turn the key to on until the fuel pump stops priming (assuming it works)). If it drops really fast you have a leak somewhere. Next, I removed the cover under the fuel fill cap to expose the rubber feed and return lines to and from the fuel rail. I forget which is which, but it is really easy to figure out.

First, prime up the system, and while it still has pressure, pinch off the feed. I used little vice grips with the tips wrapped in duct tape so as not to damage the lines. If the gauge continues to drop, it isn't in the fuel tank (pulsator or check valve). That means it must be the fuel injectors or the fuel pressure regulator. So next, pinch off the return line. The fuel pressure will go really high, but see if that slows the pressure drop to a normal level (which is minutes, not seconds). If it slows, it is the FPR, if it drops just as quick, it is the injectors leaking.

Good luck. If you have a FSM handy, that would help. I am just going off the top of my head, but they may have a different order of operations.

 

Ohming the injectors isn't going to tell you if you have a leak, only if you have a bad injector coil. The procedure I gave you is what the F.S.M (factory service manual) recommends (to the best of my memory).

 

first step ...repeat: first step...when trouble shooting any efi engine is to hook on a pressure gauge to the test port on the fuel rail...you can buy a tester kit at harbor fright for under $20...should get abt 40 psi as soon as key is turned and hold min 10 psi after 12 hr sit with key off.

if you wanna throw parts at it, based on symptoms you report, start with the ignition module inside the distributor.

 

go to work,

thanks a lot for that procedure... I have the manual and the AIM for my 80 but haven't got the 87 yet, just bought it and working on it slowly...

thanks again
tk