Den14

Do the diagnostic run down on the ICM. Should be 4 wires going going to it on the harness. Check for power and continuity as well as the ground.

playsdixie

your really need to check fuel pressure...see that it pressurizes and stays up while starting/running... your fuel line could be separating in the tank above the fuel pump...a pressure guage will tell you a lot....

oldgringo

Continuing the process. Replaced fuel pump and can now hear the pump priming, etc when the key is on. Still won't fire. Have no been able to check pressure on rail yet but will replace fuel filter first (when the weather is drier, as car is not in a garage!). Narrowing down the problems!!

blurooster

I put about a quart of gas down the throttle body and it finally caught....not at once....
still think the injectors are gummed up, after this tank with cleaner I will go plugs and wires

oldgringo

Two steps back. Got fuel pressure tester - but now, cannot hear the new fuel pump, and have no pressure. Can hear the new relay click, so will start back down the checklist again.

Den14

Since you don't hear the pump priming, at least use a circuit tester or multi-meter to ensure you have power to the pump. If it is new ( not that you can't buy a defective one ) check the fuses and continuity. Go back in and make sure you have the pump plugged in again. Check the harness that is outside the tank for continuity as well. Eliminate the obvious before throwing parts at it.

oldgringo

Den14 - Replaced the fuel pump again this morning, as well as the fuel filter. Could hear the pump cycling on when I turned the key. Primed the plenum and got 20lbs of fuel pressure - car fired but did not start. Continued to prime - same results - except now there is no pressure at the gauge. Double checked the filter (it is not leaking and is in the right direction). All hoses in/around the pump appear tight and in good shape. Cannot find any leaks anywhere - but cannot explain why I have no pressure. There was certainly air in the line, as the line bled back when I changed the filter, but I would have thought after priming/starting several times, it would have pushed the fuel up. Put another 5 gallons in the tank to make sure there was plenty of gas.

Other than continuing to prime/start, any suggestions? I'm running out of things to check.

Den14

This may seem simple, but I did this before. Check to make sure the gauge is properly sealed to the Schrader valve. If the pump is priming and you got some pressure once, there is no reason it would not get pressure again. 20lbs is about half of where you need to be though. From there I would check to determine if any of the the fuel feed lines are plugged or pinched off. The fuel pressure regulator may be suspect as well. A leaking injector can also cause pressure loss. Pull the plugs one at a time and inspect them, looking for fouled or saturated conditions. I am not fully familiar with your year, but these are some places to check. When you replaced the pump, did you replace the strainer as well? when you changed the filter, is it facing the correct direction? The pump is still running for about 2 seconds when you turn the ignition on, without trying to start it? Start chasing it from there. If the ECM is not getting correct info to start within that initial time it will shut off the signal to the injectors to prevent flooding. There should be a vacuum hose coming off of the FPR, going to the intake manifold. Pull the hose off and smell the end of the hose. If you smell any gas in the hose, you have gas in the oil pan and you should not try to run the car without changing the oil and filter. That would also lead me to think that you have a bad injector. I am around all day today to celebrate the 4th and it happens to be my B-Day, so it's a sit around and have a good time day. I am more than happy to help you with what I can. The Forum has been very good to me, so it's a good time for me to share what I have learned along the way. Keep me updated as you tackle what I have thrown at you. There are some other things to check, but start with these. Good luck and don't give up or give in!

oldgringo

DEN14 - will give it a shot. BTW - Happy 4th and Happy BDay.

Den14

Right on! Thank you much! You have a great day and try not to cut any knuckles on the car! I am cursed with the slipping wrench syndrome and have the scars to prove it! Keep up the work and it will pay off my friend.

oldgringo

Finally took it in to the shop. Eight new injectors later and a drained tank, plus a few incidentals (and $2200) - Vette runs like a champ, alternator charges, and A/C works. Now just have to put the dash back together.

Going to Body forum to see if an '84 C4 hood assembly will fit onto my '89. Tree fell on mine 41/2 yrs ago, cracked it in a few spots, but punched a fist sized hole in the hood (right over the plenum/injectors). I can get the complete hood for $175, which is a great price - unless it won't fit my '89.

Den14

I believe the 84 is a one year only fit. You should go with an 85 or newer. I think the main difference is the ducting in the hood. I am not sure if it would clear you intake assembly.

VikingTrad3r

subbed. keep going gringo!

if you shot fuel in through the intake how does that prove the injectors are working? was't it running from the fuel shot in through intake?

woody41

I had the same issue, replaced the entire ignition system, fuel system from pump to injectors, TPS, MAP, Coolant Temp sensor, no codes, no change, still no start, ended up being a collapsed pre - cat. Replaced Y pipe and installed new single high flow cat. Along all the other new parts it is running real nice....91 6 speed.

joendoodle

These symptoms sound familiar.. I got a fuel pump and filter I was about to pull the injectors but I ran SEAFOAM thru it & it cleaned the injectors...

https://www.corvetteforum.com/forums...201018:yesnod: