90 L-98 383 All new: Super Ram, MSD distributer with external Blaster SS coil, Racetronix Walbro fuel pump, 24 lb FIs, Holley AFPR, plat. plugs, new 8.8 spark plug wires, TPS, IAC, 58 mm TB.

No idle yet.

Following Helms diagnostic charts.

tests so far:

got spark on all spark plug wires. NOID lite OK, FI resistance, OK, Spark strength at least 25kv, not consistant at 28kv. Am checking on this to see if adequate. No codes, just 12s flash on ALDL grounding. Plugs examined show some carbonization from start attempts. not wet, new fuel filter. AFPR: No fuel in vacuum line.

I havn't checked FI for leaks yet. for I will have to pull off the Superram, which i dont want to do if i do not have to...want to completely eliminate the FP first.

I need to test my new Walbro fuel pump. It runs for the 2 sec at ignition. Then FP drops immediately from 40 to 0. clamp tests at both return and feed lines show pressure does not hold.

Helms says there is a fuel pump test connector beneath the master cylinder near the battery. What does this look like? Helms says to apply 12 v to it with a fused lead. how does one do that? I take it I cant just hook a car battery up to it

In a search here, found that CFI-EFI had advised that one could apply 12 v to ALDL connector G. to see if pump runs. How exactly does one go about that?


Thanks all!

 

You have not fired up yet? I'm sorry for this..
As a owner of a 90 with a 383 ...wit SR .. i'm with you.
Mine fired up at the first attempt. :o
Sorry I can't help you on your questions. Consider this a 'TTT'
-Beppe-

 

I appreciate your bump and sympathy. I have been working on this car since last Halloween, and can not WAIT to get her going. I even missed Bloomington Gold because of this....

im making arrangements to get her towed to a CF member to work on while I am on vacation next week. So im hoping i come back to drive her.

 

The test is over. The fuel pump is OK. It pressurized the fuel system when it was on. That is what the fuel pump is supposed to do.

You have proved that the injectors are leaking. There are three ways for the fuel pressure to escape.
1.) A bad regulator, that won't hold pressure.
2.) Leaky injectors.
3.) The check valve in the fuel pump.

When you clamped the return line, the pressure dropped, eliminating the the regulator as the cause. That leaves the injectors and the check valve. When you clamped off the feed line, you eliminated the check valve. ASSUMING you performed the tests properly, the process of elimination points at the injectors.

That is not in MY Helms. No comment. Maybe it's a year difference thing. Is this instead of terminal "G" in ALDL?

Start by hooking up one end of a wire to a 12 volt power source. The battery would work. Touch the other end of the same wire to terminal "G" in the ALDL. That is one way, one could go about that. BUT!!! In the first paragraph that I quoted above, you've not only proved that the fuel pump runs, but that the fuel pump relay is working, also.

RACE ON!!!

 

CFI, you made my day and took a load off my mind!

My Helms indicates that there is a fuel pump test point of some kind underneath the MC, and down behind the battery. It is also diagrammed in the Code 54 section, as having a red wire that runs off a fuel pump relay. I'll look for it tonite again and see, although its moot. I'll try the other method if needed:

Follow Up: You said that the tests have shown the Fuel Pump is OK. i have read that some FP dont have check valves...thus, would a faulty check valve cause a no start situation?

It said nothing about terminal G on the ALDL, i got that from one of your previous posts.
Thanks very much....looks like tonite its SR plenum removal time, (GROAN).

I'll speak for many of us here: we couldn't do without you here on the CF.

 

It is not needed. All you can do by powering up the test point near the master cylinder or terminal "G" is test the pump. You "tested" the pump, and it passed, when you heard it run and it pressurized the fuel system. My guess is that your "test port" below the master cylinder, is a revised location for the terminal "G" in earlier cars. Either way, you are beyond that point. forget it.

Not yours. A faulty check valve allows the gasoline and pressure to flow back into the tank. That would show up as a pressure drop, like you have observed. BUT, you had the pressure drop even with the supply line clamped off. That proves that the pressure is being lost somewhere else. Otherwise, why did you pinch off both the feed and return lines?

RACE ON!!!

 

Your logic is on target thanks once more!

 

Did you check that the pump was running when the car was on? Mine seems to not run after I turn the ignition even though it charges before the starter runs. Did you inspect your injectors? Were they dead? My car starts and runs but the fuel pressure drops like there is no fuel coming from the pump. Just wondering.
-dave