Fuel Pump? Not -- help.

[dare2bgr8]

Got a problem with 97.5 V6 3800 Supercharged Regal.

1.) Car Was running but stalled out the other day.
2.) When ignition is turned on, car starts and runs fine for a few seconds and then stalls out again.
3.) Seems like a fuel pump problem but you can hear the fuel pump turn on when you turn on the ignition. Bought a fuel Pump and changed it - No dice.
4.) Car will stay running if you keep pumping the accelerator to the floor repeatedly but soon as you try to idle or throttle it down -- it dies.
5.) Thought it could be a relay so I bought one and swapped them out - no dice.
6.) Tried a fuel filter, motor ran for about 45 seconds fine then did the same thing.
7.)Bought an Idle Air Control and swapped that out - no change.
8.) Checked the fuel and it is fine.
9.) Have AutoTap and plugged in and found no significant DTCs.
10.) Have ordered a Ignition Control Module and a Fuel Sender resistor kit. Those will come in a day or so. Hoping to send the ICM back - that's $205 more than I need to spend.

It starts up just fine -- normal start-up. Runs for a couple seconds and then dies as if the ignition were just shut off. No coughing or sputtering or anything unusual. After it dies, the fuel pump starts up just like it should. Every time you turn on and off the ignition, the fuel pump starts up for the 1 or 2 seconds. When you turn the ignition to start, it will do it all over again -- Startup, run for a few seconds, shut down.

If you try pumping the accelerator, motor will run as long as you are flooring it. Plus, there is a rev-limiter on this so when you hit the peak RPMs, it backs off the fuel until it is below RPM Limit. But again, as soon as you try to come back down to normal idle or RPMs, it just shuts down.


Any techies out here have any ideas as to what to check next? I have Service manuals for this motor but they seem pretty vague on what to test. All hoses and connections appear in order upon visual inspection. Haven't tested fuel pressure other than readings from AutoTap. It doesn't seem like that's the problem. The pressure is there. It's just after it starts running it just dies.



Thanks for any help.

 

[JasonGS]

Man, you should have asked first. It would have saved you time and money! These sypmtoms sound very typical of the fuel pump resistor. These are fairly common to become faulty. The fp resistor allows the fuel pump to operate at 50% during low RPMs. All you need to do is bypass it. The only downside is that the fp will operate slightly louder when idling, but I personally don't even notice it (yes, I bypassed mine).

First you need to locate it. It is kinda located behind the battery in the passenger fenderwell. Take the passenger side headlamp off, and look for two wires going to a white 1"x3" block. This is the fp resistor. You may need to look from underneath the car to see it, but it is in that general vicinity.

Now, you can either replace it (sorry, I don't have a p/n), or you can simply bypass it. To bypass it, snip the two wires just before the resistor, splice and cross them, and electrical tape them together. That's it. If this is the problem (which I'm fairly confident it is), then the car should start up and run fine. I hope this helps.

 

[dare2bgr8]

Thanks. It sure does sound like the problem. Well, I don't really mind the money and effort to this point. Couple hundred bucks total isn't too bad. Could have sent it to a dealer and they would have most likely done all the same stuff and charged me a $1000 to replace the resistor.

Seriously, I guess these resistors are kind of exclusive to the 97's or so. The guy at Jim PACE Gm Parts Wearhouse seemed surprised it had one. I did buy the kit for it and that s/b here in another day but I will try the bypass before then.

Actually, I did ask -- but not here. I have a '98 Z28 and am a member on the LS1 website. I posed the question there and got good suggestions. Like I said, I have service manuals. Even though they are for the 98 Camaro it includes all the info on the 3800 series V6 which comes w/the Rally Sport -- doesn't list a resistor though that I am aware of -- I will double check that.

Anyway, someone on the LS1 site just pointed over to this board -- I never realized it existed until now. I have to admit, I've gotton great info on the LS1 and it seems like this site is all as good.

So far I am into (the wife's car) for:
$ 12 Fuel sender relay
$ 12 Fuel Filter
$ 32 Idle Air Control
$ 29 Fuel Pump Resistor Kit
$125 Fuel Pump
====
$210 Total

I can deal with that. I eliminate the obvious and the cheap solutions first. Sometimes it works in your favor...sometimes not. The fuel pump was actually a steal. That lists for $500, sells for $320 at Consumer Auto Parts (local chain) but Pace had it on sale for $125 and only had one. It was actually cake to put in since the Regal has a service port in the trunk.

I got two new tools out of the deal too - never argue with a new tool. Got a pair of nice Snap Ring pliers and Torque Screw driver set.

Oh well, Wish me luck. Thanks for the advise. I believe the resistor is the ticket. It makes sense.

 

[JasonGS]

Originally posted by dare2bgr8
The fuel pump was actually a steal. That lists for $500, sells for $320 at Consumer Auto Parts (local chain) but Pace had it on sale for $125 and only had one.

Wow, that is a steal!

So, if you decide you want the wife's car to go a little faster , check out my sig.

Glad to be of help.

 

[dare2bgr8]

Don't you know it. I did check out your ride and your mods. Definitely sweet. You gotta' love it...

Dare owns:
98 Camaro Z28
97.5 Buick Regal GS
2002 Chevy Suburban

Obviously no skimping when it comes to power and everyday driving. I gotta tell you, those supercharged V6's are rockets in themselves!

I've done some of the mods on the Z28 but never really thought of doing them to the Regal -- until now. Can never have too much I always say.

Anyway, I'm going to install the resistor now. I believe you were exactly right. I took that sucker out and threw it on the multi tester and it is dead alright.

Talk about Job security on that one. Like someone's going to figure that one out. I can just picture the Dealer Mechanics treating everyone with this malfunction to a new fuel pump for $500 plus labor.

The Connection was right where you said, behind the battery. All you see is a connection coming out of the wiring harness. Which then leads down through the wheel well and the resistor bolted up onto the frame -- nice and out of sight. And they used like a 5 mile bolt to hold the damn thing on too. So not only do you have to snake your hand up between the wheel well and frame, but you also paralyze your wrist from a 1000 quarter turns with the ratchet.

Needless to say, mine was definitely gone. It had a piece already broken off and when I snaked my hand up to plug the socket on, another sliver was just hanging and the porcelin cut a nice gash in my finger tip. We've had some real cold weather here in New England and I'm sure with it already broken, water from a puddle froze up underneath it and undermined it and it finally shorted out.


Anyway, Thanks for the advice. I really appreciate the help.

 

[Kevin Turch]

My resistor went out a few months back, unfortunatly i knew nothing about this and sent it to the dealer, they charged me 100 bucks total.