After advanced search discovered this thread
https://www.corvetteforum.com/forums...acement-2.html
Lots of great info, have L98 in my C3, just replaced the entire fuel system from road race tank to rebuilt injectors, engine no start.
Verified spark w/ timing light
temporarily driving my in tank fuel pump w/ external battery to check for leaks and set fuel pressure 44-46 psi
Old system had external pump, would run a few seconds to charge up system.
pulled connector from injector, no power coming to injectors when cranking using 12vt test light
My question--- is the ECM not seeing the fuel pump ? Then not sending power to the injectors?
Thanks, Bill

 

You should have 12v to the injectors directly from the inj fuses when the switch is on. The ECM pulses the ground side to complete the circuit. Check for power on one side of the connector to ground. If good check all ECM grounds.

 

First thing I am going to do is change all fuses, never had power to fuel pump or sender after the install, been sitting for 4 years

 

Grounds could definitely be a problem. love me a wire brush and dielectric grease.

 

What year fuel system? ECM sends prime signal to fuel pump, at key on. The distributor sends signal to ECM for injector pulse, purple wire of 4 wire connector. If ECM is looking for VATS input you will need PROM with VATS disabled.

 

thinking i need fuel pump delete? kind of late to de cipher this right now...... thanks for the input
Billz

 

Thats what I am thinking, didnt know the terminology

 

85 only year corvette TPI without VATS. F body wouldn't get VATS until 87.

 

There is a oil pressure switch which signals no oil pressure, not sure what years but my 85 had it. When it failed the car would not run.. just a thought

 

I let my C4 sit for a couple years and I found that there was no power to the Fuel Pump or anything. At my fuse panel it showed a reduced voltage (a.k.a. a Voltage drop) so I went to the battery and started there. I found on my 1988 C4 there was a post behind the battery under the side panel. This post has a red wire coming from the battery and supplies power to this post I mentioned. The rest of the terminals were the fusible links connectors. After much cleaning and re-installing the Voltage drop was gone and I had full power at the fuse panel.

I started testing the fuse outputs on my panel and it seemed that the fuses had developed some corrosion which kept them from conducting the electricity. A few minutes with a points file and Emory cloth and I was able to get full voltage and power through the fuses. I replaced the fuses from a reputable auto parts store and re-installed the new fuses in place of the previous set and suddenly even my radio had full battery voltage available.

Start with clean battery terminals and follow the red wires to where the Fusible links are located on your C4. After cleaning the parts I coated them with battery grease to keep them from oxidizing again.

Don't forget to check your ground straps as they too are very important to the C4's design. I saw a broken ground strap near my muffler and after fixing it my Radio's antenna was able to work again....

Best regards,
Chris

 

Thanks guys, going to check fuses and connections first working my way from the battery, and check oil sending unit.
Bill