So my bird has recently not been starting. I have tested the fuse, which was good. When I tested the fuel pump relay wires i had multiple that was grounded and no wire that was hot. Is this correct? How would I be able to test the relay by jumping the wires? I did find one post stating how to test it but the wiring isnt the same color so im not sure.

1989 Pontiac Firebird 2.8l V6 Automatic

Any information is greatly appreciated!

 

Your first check will be to check the orange wire at the relay for +12V , which should be present at all times (regardless of whether the ignition key is on or off) . If there is no power at the orange wire, your second check will be the fender mounted fuse (20 Amp) which is in a black holder on the passenger's side fender, near where the charcoal canister is. As to the wire colors, know that in the 32 odd years since your car was built the wire's colors may have faded, I'm enclosing the wiring diagram for your engine which includes the fuel pump relay and shows the colors the wires originally were ......

 

No power to the orange wire at all. Not really finding the fuse though. It's by the battery right?

 

No, it's not near the battery if you have a 1989 V6. Your battery should be on the left (driver's side) of your car and the item in question will be on the right (passenger's) side. I will post two pics that are gonna steer you right to the fuse, just remember that while fuses sometimes do fail without being overloaded, the usual reason they blow is that something overloads them. If it's blown, and a new 20A replacement blows again, further troubleshooting will be needed (to find the excessive current draw) .....

 

Awesome. I will look at it this evening. I know when I tested it my tester said it was grounded.

 

If you were to remove the fuse and put an ohm meter between the orange wire and ground, you may well obtain a resistance reading due to the orange wire feeding constant power to the ECM (as seen in the wiring diagram) to keep it's "memory" alive ( the stuff it "learns" about fuel trims & such). What you'd ideally see would be some type of resistance, but not anything close to 0 ohms. Anyway, tonight post your results with the fuse and hopefully you are one of the (rare) lucky ones who had a fuse that blew prematurely.....

 

I sure hope so!

 

Now, in the unfortunate happenstance you DO have a genuine short circuit taking out the fuse, some of the first places to check will be any work that has been done that is not "factory", things like aftermarket radios, alarm systems, remote starters, and the like. The sad truth is that a lot of people who install such devices do a pretty crappy job of connecting the wires and that makes such installations a prime suspect for short circuits.

 

well it was working just fine a few weeks ago then out of no where no pump. So wondering if the relay was bad then I checked the plugs and found that. I'll let you know later on.

 

Ended up being the fuse in the exact location you posted. Thank you!

 

well the relay has gone back to working again after replacing that fuse. only issue I'm having now is I can't seem to get her to start when its cold out still. It does have a Cold Start Switch but it was replaced last year. If I put a heater in my garage and let it sit all day, it will start. Is it possible that the Cold Start has a fuse of some kind? Getting a code 34 as well but pretty sure that is unrelated.

 

Hi Grizz87, look at the wiring diagram I posted back in post #2. On the top left of the diagram, just under the distributor, you'll find your cold start injector circuit. Your first check should be the 3 amp "crank" fuse, if that's blown it'll cause your CSI to not function. Using an automotive test light there should be power on both sides of the fuse while the key is turned to the start position.

 

3 Amp in the vehicle under the steering wheel correct?

 

Sorry for the out of focus pic, it's a random pic I grabbed from a different thread here at TGO, yes it's in the fusebox under the dash and it's the purple 3 Amp fuse labeled "CRK"

 

yeah all the fuses are testing out good. pump itself isn't wanting to prime so may be a failing pump. i have had a new one for a while just haven't done it yet. guess i have to now. I will update after it is changed out. Will probably be Friday or Saturday.

 

If the pump doesn't do the two second prime, and the car will eventually start with prolonged cranking, the likelyhood is that it's not your pump that's at fault, but instead the fuel pump relay (or ECM) are where the problem is. If you look at your fuel pump circuit you'll see that there is an oil pressure switch that will close and provide power to the pump once the engine builds oil pressure. What you need to do is to put a test light across the dark green/white and black/white small gauge wires connected to your fuel pump relay and turn the key from off to on and see if the light lights for two seconds. If yes, next put the light on the large gauge tan/white wire (with the other end of the light well grounded) and again switch the key to the run position and see if you get 2 seconds of light. The results of those two tests will determine your next steps ....

 

ok i will test that this weekend. honestly i may just replace the pump and the oil pressure switch since as far as i know they are still original. i will update this weekend. Possibly Friday.

 

just an update. Changed out the fuel pump and the strainer. Car is starting now. Getting a cod 34 though. MAF was tested on another car and it ran fine. Is there any fuses for it?

 

To check your MAF the first check will be the MAF relay. It is mounted on the right hand (passenger's) side next to the radiator . With the key on check the pink/black wire for +12V. Next, check the light blue wire for +12V . The schematic I posted in post #2 shows the MAF circuit at the bottom of the drawing . It's not likely to be a fuse since the two fuses protecting the MAF relay circuit also protect other things that you would notice for sure if they were out (The relay's primary side is protected by the gauges fuse and it's secondary side is protected by the fender mounted fuse that protects among other things your fuel pump) .....

 

12v on black/pink and the light blue. May just replace the relay. It's pretty cheap

 

If you have +12V on the light blue with the key on (with the MAF plugged in) then the relay isn't your problem.

I have run into instances where a MAF that will work in one car won't work in another. I do not know the reason for this, just that I've seen it more than once. Some slight differences in ECMs perhaps ....

 

hmm. Any way to test maf?

 

Sadly, no, there is no way that I know of to bench test a MAF.

 

Although, something else to consider here is this;

The MAF code means the ECM is either seeing no signal from the MAF, or that it's seeing readings that don't coincide with the readings it's expecting to see. How is the rubber boot that connects the plastic air duct to the manifold, any rips in it? Or are there any other places where vacuum may be leaking, rotted emissions hoses and the like? If anything is causing air to get into the intake beyond the MAF it will be air that the MAF hasn't measured, and will skew the readings between what the MAF is telling the ECM about how much air is moving through the system VS the actual amount of air (air through the MAF plus the leaked in air) ....