[SSJason]

I will start off by saying that I have spent the better part of my days from before Christmas searching and reading all the threads I possibly could on my issue here but am still at a standstill. With that being said, here I go...

I have a 96 Impala SS with 156k and about a year ago it just died on me while driving on the interstate. I figured the fuel pump was going out as it had intermittently did this before but it would always fire back up after sitting for about 10 mins. This time was different as it didn’t start up. I’ve had a couple buddies that are mechanics check it out and both said, “It’s your fuel pump. The engine isn’t getting any fuel.” So, I drop the tank, replace the fuel pump and sending unit as it looked to be original and figured I’d just replace with new (Autozone) unit. Replaced fuel filter as well. Thought it would fire right up and I’d be cruising again but no such luck. I read on another thread it could be FP relay so checked/replaced that, still no luck. Then checked PCM fuse next to FP fuse. BINGO... blown! Replaced that for it to immediately blow again. FP doesn’t even run and I’ve noticed my gauge cluster lights aren’t working. All other dash lights are, though. I’ve read that it could be the coil, ICM, grounded wire or a bad ground somewhere. I’ve checked the ground to the head at the ICM and on the trunk hinge and they are good. Without throwing more money at parts I don’t need to replace, what are your thoughts/ideas/recommendations? I’m prideful of working and fixing my own vehicles (plus, can’t afford to take it to a shop for repairs) so ANY guidance is greatly appreciated. Judging by the amount of threads on this issue, I hope someone has THE answer for me. Thanks in advance, patiently waiting...

 

[96 Black]

".....Then checked PCM fuse next to FP fuse. BINGO... blown! Replaced that for it to immediately blow again......"

It would appear you've got a short to track down first.

 

[SSJason]

".....Then checked PCM fuse next to FP fuse. BINGO... blown! Replaced that for it to immediately blow again......"

It would appear you've got a short to track down first.

I figured as much but do you know where I’d start from?

 

[96 Black]

Whatever is a fulltime hot to the PCM, and branch out. This may help:

A

 

[Z09B4U]

Please clarify are talking about fuse #2 or fuse #5?
Does it blow when you put it in the fuse holder or after you turn the key?

There is a test connector for the fuel pump on the passenger fender, and ways to test the pump from the pump relay. Did anyone try?

If it is fuse #2 blowing after key on try removing the fuel pump relay, then new fuse and key on.
If it is fuse #5 blowing when you put it in try unplugging the ignition coil then new fuse.

Fuse #2 PCM and fuel pump.
Fuse #5 PCM coil, and transmission.

 

[SSJason]

Please clarify are talking about fuse #2 or fuse #5?
Does it blow when you put it in the fuse holder or after you turn the key?

There is a test connector for the fuel pump on the passenger fender, and ways to test the pump from the pump relay. Did anyone try?

If it is fuse #2 blowing after key on try removing the fuel pump relay, then new fuse and key on.
If it is fuse #5 blowing when you put it in try unplugging the ignition coil then new fuse.

Fuse #2 PCM and fuel pump.
Fuse #5 PCM coil, and transmission.

Fuse #5 is the one blowing.
I did not know #5 covers PCM, coil, and transmission so thank you!

 

[SSJason]

Fuse #5 is the one blowing.
I did not know #5 covers PCM, coil, and transmission so thank you!

And yes, blows after I turn the key to “ON”.

 

[SSJason]

Where exactly is the red fuel pump prime wire? I’m not seeing it from my fuse box on the passenger fender.

 

[Sshockr]

The red wire should be roughly middle of the fender.

Keep in mind the #5 10A fuse feeds ignition power to the PCM, the black connector on the ignition coil, and the pink power wire on the transmission connector.

I don't think the issue is the fuel pump. The issue is the computer doesn't even know the car is turned on once that fuse pops.

-Brian

 

[Z09B4U]

Keep in mind the #5 10A fuse feeds ignition power to the PCM, the black connector on the ignition coil, and the pink power wire on the transmission connector.

I don't think the issue is the fuel pump. The issue is the computer doesn't even know the car is turned on once that fuse pops.

-Brian

100% what I was thinking in post #5. As he says once the PCM has no power nothing can happen as it turns on the pump for a on/off prime cycle then waits for the engine to rotate.

I do not see how the pump can blow fuse #5 but if you remove the pump relay it is not a circuit any more and can not blow a fuse.

No one said this would be easy. I would unplug the PCM, ignition coil, and transmission and see if the fuse survives. If it blows you have a wiring harness problem. If the fuse survives plug in one thing at a time till it does blow at key on.

While you are under the car check the transmission harness for damage, maybe something hit it, or it is loose and melted, and then the engine died.

 

[Z09B4U]

If you want to check your tank work:

To use the prime wire you need a 15 Amp FUSED 12 volt source. A old transformer type 10 amp charger(it should have a internal breaker) might get it going but a "smart" charger will not.

 

[Sshockr]

If the harness clips let go, it is very possible to melt the harness where it runs at the back of the pass side exhaust manifold. I once had to splice back together about 12 circuits in that location.

-Brian

 

[SSJason]

The red wire should be roughly middle of the fender.

Keep in mind the #5 10A fuse feeds ignition power to the PCM, the black connector on the ignition coil, and the pink power wire on the transmission connector.

I don't think the issue is the fuel pump. The issue is the computer doesn't even know the car is turned on once that fuse pops.

-Brian

Thanks. So, I’m hoping it’s either the ICM or coil. I’ll probably replace both together after I try what Z09B4U suggested.

 

[SSJason]

So, just an update... don’t know why I didn’t check once I got it out but the old FP wiring was fried in the tank. Not sure if that helps narrow down the issue at all but I hope to get back to it tomorrow. Dang flu.

 

[C.T.]

I will start off by saying that I have spent the better part of my days from before Christmas searching and reading all the threads I possibly could on my issue here but am still at a standstill. With that being said, here I go...

I have a 96 Impala SS with 156k and about a year ago it just died on me while driving on the interstate. I figured the fuel pump was going out as it had intermittently did this before but it would always fire back up after sitting for about 10 mins. This time was different as it didn’t start up. I’ve had a couple buddies that are mechanics check it out and both said, “It’s your fuel pump. The engine isn’t getting any fuel.” So, I drop the tank, replace the fuel pump and sending unit as it looked to be original and figured I’d just replace with new (Autozone) unit. Replaced fuel filter as well. Thought it would fire right up and I’d be cruising again but no such luck. I read on another thread it could be FP relay so checked/replaced that, still no luck. Then checked PCM fuse next to FP fuse. BINGO... blown! Replaced that for it to immediately blow again. FP doesn’t even run and I’ve noticed my gauge cluster lights aren’t working. All other dash lights are, though. I’ve read that it could be the coil, ICM, grounded wire or a bad ground somewhere. I’ve checked the ground to the head at the ICM and on the trunk hinge and they are good. Without throwing more money at parts I don’t need to replace, what are your thoughts/ideas/recommendations? I’m prideful of working and fixing my own vehicles (plus, can’t afford to take it to a shop for repairs) so ANY guidance is greatly appreciated. Judging by the amount of threads on this issue, I hope someone has THE answer for me. Thanks in advance, patiently waiting...

I will start off by saying that I have spent the better part of my days from before Christmas searching and reading all the threads I possibly could on my issue here but am still at a standstill. With that being said, here I go...

I have a 96 Impala SS with 156k and about a year ago it just died on me while driving on the interstate. I figured the fuel pump was going out as it had intermittently did this before but it would always fire back up after sitting for about 10 mins. This time was different as it didn’t start up. I’ve had a couple buddies that are mechanics check it out and both said, “It’s your fuel pump. The engine isn’t getting any fuel.” So, I drop the tank, replace the fuel pump and sending unit as it looked to be original and figured I’d just replace with new (Autozone) unit. Replaced fuel filter as well. Thought it would fire right up and I’d be cruising again but no such luck. I read on another thread it could be FP relay so checked/replaced that, still no luck. Then checked PCM fuse next to FP fuse. BINGO... blown! Replaced that for it to immediately blow again. FP doesn’t even run and I’ve noticed my gauge cluster lights aren’t working. All other dash lights are, though. I’ve read that it could be the coil, ICM, grounded wire or a bad ground somewhere. I’ve checked the ground to the head at the ICM and on the trunk hinge and they are good. Without throwing more money at parts I don’t need to replace, what are your thoughts/ideas/recommendations? I’m prideful of working and fixing my own vehicles (plus, can’t afford to take it to a shop for repairs) so ANY guidance is greatly appreciated. Judging by the amount of threads on this issue, I hope someone has THE answer for me. Thanks in advance, patiently waiting...

We had the same problem. Two fuel pumps later, we removed one of the relays. So when it shut down, we would have to jumper it. Don't remember which relay. Took it to a shop that mainly did electrical work. Steve resoldered all the contacts for the fuse block. It has not cut off again
That's been over 15 yrs ago. 96 Chevy Impala SS. I hope that you have it figured out

 

[SSlow94]

Make sure you check the bulkhead that the in tank and external fuel pump harness plugs into for burnt/charred pins along with the ends of each harness.

 

[SSJason]

UPDATE
After replacing multiple parts, the culprit was the ICM. Thanks Z09B4U, your guidance helped me find the problem. My car is on the road again!