Mike Kamholz

This just started 2 days ago I was decelerating and the engine just stoped. There was power to everything and I was able to start it up before the car got to the stop sign. It has happened 3 times not all at low speed and will start right up. 88 corvette. Any help would be nice. Oh by the way. The tank had about 1/4 left

billschroeder5842

When it dies, does it feel more like it is running out of gas or does the ignition just cut out and do the dash light stay on after it dies,

This will tell us if it is more electrical or fuel related.

Mike Kamholz

Everything stays on lights radio all good. Just stops and continues to coast. But will fire right back up. There is no lunging or hesitation just cuts out.

Mike Kamholz

Any chance it could be the fuel pump cutting out what would that look like??

billschroeder5842

If it only happens on deceleration, my guess is that it is the fuel pressure regulator. The FPR is vacuum operated (adjusted actually) and the decrease in engine rpm lowers the vacuum, closing the FPR and limiting the fuel flow.

Acceleration and normal speed apparently gives tyour FPR enough to "hold" steady. If the car accelerates normally and drives steady just fine my guess is that your pump is doing its job.

You can always check your fuel pressure and bench tests the FPR with a gauge. Put the gauge on the schrader valve and increase the speed at idle. Keep an eye on the the pressure. Then release the throttle to idle and see what the pressure does- it should remain pretty steady.

Just my guesses at this time...

Mike Kamholz

Ok I will give it a try thanks.

Mike Kamholz

Ok have not checked the fuel pressure yet. But did replace the ICM as I have read they they can go out. So far 40 miles and all good.

81c3

My guess is you added more fuel to the tank....???? If you did, maybe the problem is in the fuel tank at the rubber fuel line connecting the hard line of the fuel assembly unit to the pump itself. Its about a 4" section of fuel line that could be split.

JasBass

I went through this exact same situation with my 89. Car would run amazingly strong as long as I was cruising or getting on it. As soon as I would let off and put the clutch in to cruise, RPMs would just trickle down and stall out, electronics all still on and would fire back up. I tracked it down to a bad FPR, pressures would drop under acceleration and then fall more once it let off. Pressures in the rail would bleed down to 0 within minutes. I replaced the FPR and pump since they were both original pieces. All in $70 fix and an afternoon of time.

I had a friend of mine with an L98 vette that had a similar issue as well. Turns out multiple of his original Multec injectors were sticking and creating a rich condition at lower RPMs and stalling the car. Just more food for thought.

I'm curious about the ICM fix though, my next project is replacing the electronics in the distributor. My idle gets a little lumpy after some heat gets in the engine.

Mike Kamholz

Yes I did but it died several times even after having more fuel it.

Hot Rod Roy

Bill, the problem may be the FPR, but we have a slight technicality here. The FPR is on the return side of the fuel path, so the FPR opens to reduce the fuel pressure, rather than closes. In the old carburetor days, with no return line, the FPR was on the supply side, so that was different.

In our 'vette's, closing the FPR would increase the fuel pressure.

Mike, we need to see the results of your fuel pressure test, and how soon does the pressure drop off?