after searching and reading all of the problematic areas of the c4 on
a "no start' condition i have found something i havent read a thread
on...
1989 chevrolet corvette convertible L98/M30
verified no codes, checked spark and pressure.. heres wher it got tricky.
i had 39psi rail pressure and itd crank and run for a split second.
so i tapped the aldl with a fused 12volts to terminal "G" and noticed
a faint fuel pump buzz. pressure slowly recovered. engine will not
start... pulled the fuel door and rubber out to check voltage and ground.
i had battery voltage (scanner showed +.2 more) but still a faint
fuel pressure and buzz. went to next connector inside the cargo area
and found the 15pin connector in a corroded mess. this houses the
rear signals and lights, fuel pump and sender signal wires. the ground
showed 405.5k ohms resistance and fuel pump was 550k. the tire lamp
was rotted from the connector on both sides. you could tell the lil
well the connector sits in is a pool from some hatch leakage.
ill repair this with some sealed metric-pak connectors and drill the
well to allow drainage.
with a temporary repair i had to lower my adjustable regulator 6.5psi
so 6years ago i already had a deteriorated condition but band-aided
it with a regulator pressure adjustment. so if you have racked your
brain, bought fuel pumps, and think you nailed it pretty good, youd
might wanna investigate this sort of error, it will detract from
performance and costly unecessary repairs later. especially the
yearly fuel pump replacement threads ive seen...

airdeano

 

Good info