Hi, I've swapped an 89 350 TPI into my 87 2.8L firebird. When key is turned on, the fuel pump doesn't prime. I've tested the relay on the firewall and it works fine. My guess is that where the engine harness plugs into the firewall (for the fuse panel) is where i'm getting a break in the signal. Does anyone have the diagrams for both the 2.8L connector and 5.7L connector (just right hand side needed as the left one is for the lights and stuff and that is the original one) I'm wondering if one of the pin out connections was moved created an open circuit. If anyone has any other ideas, i'd be interested to hear them

Thanks, KYLE

 

Sorry, also would like to mention that engine cranks and stuff like the radio DOES work

 

Are you getting power to the pump? If the relay is working you gotta be losing power somewhere between there and the pump.

 

Well, yeah, that's the point, i've got no power to the pump, and it doesn't prime when i turn the key. Everything worked before the swap, so the problem must be either at the plugs where the ECM is or where it plugs into the firewall, so one of the wire pins at those plugs must be misaligned somewhere (is my guess)...I just plugged in the new engine harness in line with the dash one as the plugs are all the same. I was wondering if anyone knew of any discrepencies from doing this. Most everything else seems to work as of now...light, trunk motor, radio, crank, just no power for the fuel pump! I didn't touch any of the other under dash wiring.
Any help is appreciated

-KYLE

 

Did you check the fuses that are mounted on the fender? It sounds like you have crank but no run, and that usually indicates no power to the ECM, or that you do have power to the ECM but not the pump. More clarification is needed here, but there is also a fuse on the main fuse panel that is for the f/p as well. Check them. Also, I know you hate to read this, but you could have a bad ECM there, too.

 

i'm pretty sure there's no power to the pump, but there is power to the ECM as i have spark, and the relay for the pump clicks after the key is on for a few seconds. My dash harness had a 6-pin grey connector beside the ALDL connector by the ECM. I understand one of these wires is a fuel pump power wire (which currently is not hooked up to anything as the new TPI engine harness did not have provisions for this 6 pin connector. The fuses are fine. What color is the fuel pump power wire coming from this 6 pin connector? Brown?? Anyways, what do i need to modify on the 87 v6 dash harness to make it work with the 89 TPI engine harness? Something's not lining up properly, at one of the ends of the engine harness.

 

does the relay click ?

 

This is a picture of the 6 pin connector (part of the v6 dash harness) which currently doesn't go anywhere. I think one of these wires is the fuel pump power. Where do I hook it up and what color is it? And where do i hook up the other wires to the TPI engine harness which doesn't have this 6 pin connector? I read that in later years, the 6 pin connector was incorporated into the ALDL connector thus eliminating it from my 89 engine harness.

 

yeah, deadbird, the relay clicks after the key is on for like 3 seconds. Do i just need to hook up the tan wire off the relay straight to fuel pump power?

 

wow... that's one large picture

That connector has no relation to the FP at all that I know of.

The relay should 'click' once with the key on and 2 seconds later click off untill the car is started.

Did you use the bulkhead harness (one next to the brake booster) from the 350 motor ?

 

yes, deadbird, i used that bulk head from the v8 ( the right side anyways, the left side is from the v6...for the lights and stuff i'm pretty sure). I noiticed on the bottom left corner (looking into bulkhead), theres a tan/white coming from the relay. This goes nowhere on the dash side. Where is it supposed to go? (sorry bout the size of that pic!)

 

heh.. I was only kidding about the pic (though it is huge).

The relay should have a heavier gauge wire (14, like the purple & red wires at the starter) that is tan with a white stripe. This should go to the bulkhead on the drivers side firewall (next to the booster).
On the inside, it should come out of the connector in relation to the underhood side.
From there, it runs to the rear of the car behind the back seats to another pass-through harness.
This comes out just forward of the gas tank (under the car, over the axle) and connect to the in-tank pump

It's sounding like the wiring to the bulkhead isn't matching up for the pump.

 

thanks a lot deadbird! So if i hook that tan/white directly to the fuel pump power coming from the tank, i should be golden!