OK, my car (87 2.8 firebird) is STILL having a problem with starting. This is driving me nuts. I just checked my fuel pressure and it reads 45 with key turned on and 40 with motor running. I turn it off and the pressure slowly decreases. I've replaced the fuel pressure regulator, coolant temp sensor, fuel pump relay, spark plugs, reset timing to 10*. I also got a error code 54 couple of days ago but car is still running. Do i need to check the injectors themselves? How do you do this? Any other ideas? It also idles a little erratically (almost a little too low it sounds like). Might be time to pay someone to take a look.

 

Doesn't a code 54 mean the ecu is bad?

 

my understanding was code 54 was fuel pump relay and no signal to fuel pump(or something like that)

 

or you have some sort of computer problem, I'd suggest a donor computer to find out...

 

I vote for that I have knoe 2 different people who have had problems with their f-body ecm's

its no fun

 

Hello Six-Banger,

There is a package in your e-mail that might help.

 

Let me see, that damn code 54 again. You have either a bad fuel pump relay, wiring, or the ECM has gone south and ain't coming back. To check, connect fused 12VDC between the top right and lower left terminals of the ALDL. If the pump works... you need to fork out the dough for a new ECM. KEEP YOUR FACTORY CHIP!

Trust me.. I finally got rid of 54 through an ECM swap, but I think both ECM's may be bad....

Also, if the fuel pressure bleeds off quickly after KeyOff, then you need to check the injectors. DON'T FORGET THE ONE IN THE BACK OF THE MANIFOLD!

Adjust TPS, check IAC valve, check vac lines. etc, etc....

 

I thought terminal G (lower left ALDL) required +12v to test the fuel pump...? Is it just a ground for the relay?

 

How do you apply fused 12v dc?

 

Ooooh.. fused 12V between top right and lower left..

Erm, correction. Top-right (ALDL Pin A) is a chassis ground. The fuse will blow immediately. Simply connect the fused +12v to lower-left (ALDL Pin G)

As for how to do this, you run a fused wire (as in a wire that has an inline fuse, preferrably rated at 10-15 amps) from the "BAT" connector on your fuse block (always-on +12V *UNFUSED* power source) to ALDL Pin G.

 

Ahem, incorrect again Smurf. You are SUPPOSED to apply the 12VDC between the ALDL G and ground to get the pump to work if it is going to (not a complete circuit without a chassis ground, right?!). I did it this way and have not changed a fuse since last April (was done in or near July).

ALDL terminal G is the fuel pump relay test circuit....

To apply the current, either grab an AC adaptor capable of 12VDC and hook it up somehow (universal type with 9V connector works with spare 9V connector from RadioShack) or get two long wires and attach them to the battery.

 

Oh, yeah, if you're using an external power supply, you'd have to ground the chassis to the external power supply also. I conceed to that fully.

My method assumes your battery works and you know how to use a jumper wire, which tends to be the more common way of testing this kind of thing.. since the battery tends to have to work for the fuel pump to spin anyway, unless you're using a rather large DC power supply and it's hooked up to the battery terminals.. in which case, the BAT pin on the fuse block is energized and the concept agian becomes rather silly..

Why exactly would you want to use an external power source to test the relay.. honestly, is there something I'm missing here? This is not sarcasm, but it does seem silly without justification since the entire car is a +12v DC power supply...

As far as the two long wires from the battery, perhaps you need to trace ALDL pin A, also.. it's literally just a chassis ground, and has nothing to do with the fuel pump.. you're not going to modify the results grounding it or not. And as far as the +12 via a really long wire from the battery... *points at the BAT terminal on the fuse block*.. it's a foot and a half from the ALDL...

 

I agree completely with everything you said, Smurf.

I was just saying the way I did the test because my batt was starting to go on the fritz at that time without a charging mechanism and was forced to use an external power source. Do it the way you are able or that you find easiest.