Fuel Pump going?

[pvt num 11]

What are the symptoms that the fuel pump is going out?

First, I ran it out of gas about two months ago. It's been driving fine since, especially after I replaced the plugs and wires. Drove superbly Friday morning, no complaints at all. Fast forward to this morning. Fuel pump whine when I place the key to RUN sounded a bit lower-pitched then normal. I didn't think anything of it - batteyr voltages could've been lower. I don't have a hot-wire kit, car is bone-stock.

Two, I was ramping up for the freeway, around 45MPH, at 2k on the tach, and the car seriously stumbled and fell flat on its face. Felt exactly like it was running out of fuel, so much that I immediately checked the gauge - neearly full. I got off of the freeway I had just entered at my earliest convenience (driving in the slow lane the whole time, as the car just wouldn't accelerate very well at all), and drove it through the back roads to my house, and parked it. Any time I tried to coax more power out of the car, it would stumble and practically die out altogether. Idles okay, off-idle is okay, but the car has no guts anymore. quicker6 is going to help me out Thursday with troubleshooting, but I was wanting some input from others who have dealt with a bad pump - what were the symptoms of it going kaput?

Thanks for the input! :smile:

 

[SlowTTA]

I would check fuel pressure first.

Sounds like the same thing that happened to me when my MAF took a dump.

 

[pvt num 11]

MAF - not fun, but I'm not throwing any codes. I'll go look into that possibility if my fuel pump pressure checks out okay, thanks for the quick reply!

 

[Lee_Burough]

You need to go HERE for your thought process as you troubleshoot your fuel system.

Look under 'Troubleshooting,' then under 'Fuel Pressure Tests.'

Steve Wood went to a lot of trouble to get that info for us....Study it carefully and you'll do a good job of testing that fuel pump and fuel system

lee

 

[SlowTTA]

I agree, the page that Steve has assembled is a great resource for any turbo buick owner.

My car didn't throw any codes for the MAF when it went, had me searching everywhere else.

 

[89ICBM]

Two, I was ramping up for the freeway, around 45MPH, at 2k on the tach, and the car seriously stumbled and fell flat on its face. Felt exactly like it was running out of fuel,
Thanks for the input!


You've got a bad MAF sensor. Fuel pumps generally have no symptoms, they just quit. Start yer car and tap on the MAF, (if you don't know, it's the black plastic thing that is attached to yer intake hose and yer air filter) you will see the motor stumble as you tap it.

 

[pvt num 11]

Okay, I'll go try that. Thanks.

 

[87GNSteve]

Do process of elimination, fuel pump in a F-bod is NO FUN!!!
ask me how I know

 

[pvt num 11]

Tapping the MAF didn't do anything. Unplugging it killed the car. Plugged it back in, then I unplugged the TPS, idle shot up to around 1400 or so. (hey, at least it idles!) Threw a code, so I plugged it back in. Drove it for a bit, still wants to die off adn sputter and cough for a bit before you can get ANY sort of power at all. quicker6 is going to bring his spare MAF tomorrow so i can try that, maybe my MAF is screwed up and unplugging it made it that much worse. Of course, he just sold his scanmaster, so we can't get any decent readings on stuff like mass air intake or anything...

I'm relegated to driving the GTA for a time, small intake manifold leak, but it drives decently and the base didn't give me a rash of crud when I got on base with it...

 

[3.8TransAM]

hehehe

I've never had a fuel pump "just quit" in either of my f-bodies the fuel pump went out on. (I also have pickup coils that were intermittnet and ign modules too)

They did all manners of stupid stuff like his is doing

That being said, do all the basic checks and verify stuff before you condemn it.

The links posted are great for that.

Fuel pumps arent too bad in f-bodies or I just have lots of experience :-(

They also like to puke after say, ummmm u fill up the tank (done that one too lol)

Use a lift if accesible or just get the entire car in the air as high as you can safely(I do all four corners)

Lower the rear as far as it will go with the tires off and undo the shocks. Unbolt the brake/fuel lines and also undo their fasteners on the trans tunnel(this get u some more clearance for lowering the rrear)

Unbolt the tank(drain it any way u can before doing this or it will really suck)

Swivel it from the frt of the car down and angle it towards the grd on the pass side and you should be able to slide the neck out(do not force it)

The only part that always gets me PO'ed is getting the actual tank neck in and out of the fender.

Swap the pump out and reverse.

check the sender for wear while u are there.

later
Jeremy

 

[pvt num 11]

Thanks quicker6

Okay, I have the spare MAF, so when I get home tonight, I'll throw that in and see if it makes any difference. I'll also try driving it without hte TPS hooked up (didn't try that last night) and MAYBE I can figure out why my car is gutless. Oh, and a fuel pressure gauge would be groovy too. Hello, Checkers...?

 

[pvt num 11]

Update!

I think I discovered the source of the problem yesterday: WATER. My airbox lid wasn't on tight, and we've had a whole bunch of rain, so I'm guessing water got in through the lid - the MAF, MAF duct, air cleaner and air box were wet - the filter was soaking wet. I had a 1/2-inch of water in the box. Took all that crud off and drove it for a bit, and yep, the car drives much better, but it didn't like the MAF missing. I'm off to rip out the intercooler and drain whatever got stuck in it. Turbo seems fine, it spins easily and it doens't look damaged in any way - I'm guessing that heat evaporated any water that may have contacted it.

 

[Lee_Burough]

I think I discovered the source of the problem yesterday: WATER. My airbox lid wasn't on tight, and we've had a whole bunch of rain, so I'm guessing water got in through the lid - the MAF, MAF duct, air cleaner and air box were wet - the filter was soaking wet. I had a 1/2-inch of water in the box. Took all that crud off and drove it for a bit, and yep, the car drives much better, but it didn't like the MAF missing. I'm off to rip out the intercooler and drain whatever got stuck in it. Turbo seems fine, it spins easily and it doens't look damaged in any way - I'm guessing that heat evaporated any water that may have contacted it.

Good going on finding that water issue....Its the simple things that bite me most often

 

[SlowTTA]

I guess water ingestion could cause a few problems. :biggrin:

Good to here you found something, I hate chasing my tail just to find out it was something simple.

 

[pvt num 11]

Great excuse to go buy a K&N filter cleaning kit - thing was totally filfthy and needed a bath anyways...! I just hope my MAF is okay - how much are they going for nowadays?

Besides all of that, if I wanted water-injection, I'd go buy a kit, dang it! :biggrin: