Fuel Pump, Resister, PCM...will it ever end?

So my 99 Regal GS (supercharged) stalled the other day. It didn't run rough prior to stalling, wife says it was just like the engine shut off smoothly. It would crank well, but not fire.
I'm no expert, so I had it towed to the local mechanic who I trust more than the others.
They said "...the fuel pump is pulling too much power and shorting out. after the fuel pump cools down we are able to restart the vehicle. need to replace the fuell pump, fuel filter and fuel pump relay."

So I shelled out the cash and got the car back. Then, hours later it stalled again exactly as before. This time, it started back up and ran fine for another 20-30 miles (then stalled, but started right up no problem...).
Also, wife says that she didn't feel like she got the same boost from the supercharger when she was driving faster than roughly 30-40 mph.
So I took it back to the mechanic, they said bad resister and changed the resister.
But the car continues to stall out (same stall, still starts right up). Now they're saying PCM.

less than 10K miles ago, MAF & crank shaft position sensors were replaced.
about 40K ago the ignition switch assembly was replaced.

So, I read things like the conclusion of this thread (last post...): http://www.automotiveforums.com/vbulletin/archive/index.php/t-882953.html
...and I really can't help but wonder if the fuel pump had any problems at all.
Are there other conditions that could cause a fuel pump to draw too much power & short out?

What brand MAF sensor did you buy? If it's a Cardone reman, they are a very high failure rate part and it could be bad again.

Does the car die while cruising, or during hard accelleration?

When a fuel pump resistor goes bad, the car will normally start, then die within 3-5 seconds when the PCM switches from high-speed mode for prime to low speed mode. The other thing that will happen is the car will die while driving, then restart after the resistor cools down (could be a few seconds or up to a minute or two).

What brand MAF sensor did you buy? If it's a Cardone reman, they are a very high failure rate part and it could be bad again.

Does the car die while cruising, or during hard accelleration?

When a fuel pump resistor goes bad, the car will normally start, then die within 3-5 seconds when the PCM switches from high-speed mode for prime to low speed mode. The other thing that will happen is the car will die while driving, then restart after the resistor cools down (could be a few seconds or up to a minute or two).

The MAF sensor was put in by a different mechanic (guy's been fixing my family's cars for 20+ years - always trustworthy). So while I don't know what brand he used, I'm confident it was new and of a respectable mfg.

The car dies while cruising. It can drive 5 minutes, then die, or 20-30 miles, then die.
And resister has already been replaced, but the car is exhibiting the same failure.

The two things I want to know the most are:
1 - if it possible for a perfectly good fuel pump to draw too much power & short out as a result of some other malfunctioning component?
and
2 - if it truly was a bad fuel pump that was shorting out, could it's failure damage the PCM?

They said "...the fuel pump is pulling too much power and shorting out. after the fuel pump cools down we are able to restart the vehicle. need to replace the fuell pump, fuel filter and fuel pump relay."

:rolleyes:

That is one of the dumbest things I've ever heard. All the fuel pump needs is 12 volts to put out fuel pressure ranging from 48-55 psi and gasoline cools the fuel pump. If it it was drawing too much current via a short it would pop the fuel pump fuse. Have you tried switching the fuel pump and fuel pump speed control relays with each other? What does the 12 volts and ground look like at the fuel pump electrical connector with ignition to ON?

Also, what brand crank sensor (CKPS) since it sounds like the CKPS is a possibility too.

:rolleyes:

That is one of the dumbest things I've ever heard. All the fuel pump needs is 12 volts to put out fuel pressure ranging from 48-55 psi and gasoline cools the fuel pump. If it it was drawing too much current via a short it would pop the fuel pump fuse.
Excellent point. Unfortunately, I don't have much of a leg to stand on - I had to have the car working to drive kids around (mine + others), go to the grocery store...etc. So I had to pay up and get it done. If I had the equipment and the time (and also time to learn), I'd put the original pump back in and test things out.

Have you tried switching the fuel pump and fuel pump speed control relays with each other? What does the 12 volts and ground look like at the fuel pump electrical connector with ignition to ON?
I know where the relays are, but where is the fuel pump electrical connector? I've seen references to alldata.com for electrical diagrams and what not - does that include information such as the location of the fuel pump electrical connector?

Also, what brand crank sensor (CKPS) since it sounds like the CKPS is a possibility too.
Same as the MAFS - I don't know, but I trust the guy who put it in.

I just got the car back this evening, we'll see if it runs normal now.
I may have had to pay for things I didn't need (and if the car runs normal, I'll probably never know) but given that I don't have the equipment or time, I guess I'll just have to accept that it's cheaper than buying a new car :frown:

Oh well, I'll stick to simpler things for now, like the tie rods that are both too worn. Those I know how to change :smile:

Thanks for your time and thoughts.

I know where the relays are, but where is the fuel pump electrical connector? I've seen references to alldata.com for electrical diagrams and what not - does that include information such as the location of the fuel pump electrical connector?

You're welcome and good luck!

See pics. The gray connector. You can access the fuel pump located under the access panel located in the trunk right behind the rear passenger seat. Easy to get to considering. The connectors are right there.

http://i5.photobucket.com/albums/y186/lizzywiz/fuelpump_top.jpg

http://i5.photobucket.com/albums/y186/lizzywiz/fpaccess.jpg

http://i5.photobucket.com/albums/y186/lizzywiz/fuelsender.jpg

http://i5.photobucket.com/albums/y186/lizzywiz/fuelpump_top2.jpg

You can access the fuel pump located under the access panel located in the trunk right behind the rear passenger seat. Easy to get to considering. The connectors are right there.

Can the fuel pump be replaced via that access panel in the trunk floor? ...ie, does the tank have to be drained and removed?

Can the fuel pump be replaced via that access panel in the trunk floor? ...ie, does the tank have to be drained and removed?

Yes and no the gas tank doesn't need to be drained or dropped. About a one hour job.

Yes and no the gas tank doesn't need to be drained or dropped. About a one hour job.

So I just called the mechanic - it wasn't in the notes, but he said that the fuel pump fuse was blown. I hadn't checked prior to having the car towed. In hindsight, checking the fuses is an obvious thing to do. Hopefully it won't escape me in the future.

And he said that there is no access panel in the trunk. I am going to look first thing when my wife gets home...

Thanks again,
-Rick

He's wrong about the access panel, as every Regal and Grand Prix from 97-up have one. If he charged you labor for having to drop the tank, he should refund you that labor, as it's not your fault he didn't know about the access panel.

As far as the MAF sensor and crank sensor issues, just because you trust your mechanic doesn't mean the parts he installed couldn't be questionable without his knowledge. Find out from him what brand he installed, if the MAF is from Cardone, have him test it again as it could be bad. Same with the crank position sensor, if he installed some Zenith or other crap part, find out.

If I had a nickel for everytime I've heard "I just replaced the ........, so that can't be the problem (but it was), I'd be typing this from my own private island in the Bahama's.

He's wrong about the access panel, as every Regal and Grand Prix from 97-up have one. If he charged you labor for having to drop the tank, he should refund you that labor, as it's not your fault he didn't know about the access panel.
Already have. I actually stopped by the shop it show it to him. It was just before closing on Sat. so he said he had to wait till today to see what they're going to do. I expect at the very least to be refunded the additional labor of dropping the tank vs using the access panel.

As far as the MAF sensor and crank sensor issues, just because you trust your mechanic doesn't mean the parts he installed couldn't be questionable without his knowledge. Find out from him what brand he installed, if the MAF is from Cardone, have him test it again as it could be bad. Same with the crank position sensor, if he installed some Zenith or other crap part, find out.
Well, the car is working well now (after the fuel pump and the PCM). But I will take your suggestion and find out the mfg of the MAF & crank position sensor, just so that I know going forward.

If I had a nickel for everytime I've heard "I just replaced the ........, so that can't be the problem (but it was), I'd be typing this from my own private island in the Bahama's.
My grandpa taught me long long ago never to rule out anything when troubleshooting, and that has done me well. So yeah, I hear ya!

Where is the resistor located?

Where is the resistor located?

Behind the passenger side headlamp in the inner fender part.

Hi, I don't know if this will help - U have to check around if GM still does this. I have a Regal Limited & my car was do'n the same thing. I recently found out that if the oil pressure sensor/switch goes bad or starts to leak it will automaticlly shut down the fuel pump.

Hi, I don't know if this will help - U have to check around if GM still does this. I have a Regal Limited & my car was do'n the same thing. I recently found out that if the oil pressure sensor/switch goes bad or starts to leak it will automaticlly shut down the fuel pump.

Welcome to AF.

Thanks for contributing. Not in the '97 and up models. The oil pressure sending unit does not affect the feed to the fuel pump relay to shut down the pump.