We are having a problem with cranking but not starting, or just shutting down for lack of fuel (apparently). The pump does not make noise with the key on when this happens.

I am about to put in another new fuel pump on the 4th of July. In December (Sub Zero here in the Chicago area) The 1996 Bonneville SLE stranded my son Nate several times, before getting it towed to a local dealer. $700 later, it had a new fuel pump and sending unit. Last night, it stranded him again.

It was too cold to get under there ourselves last winter, but "poor people have poor ways", and we have to do it ourselves. It started today after we had it towed home, every time, all day, but I don't think it can be counted on. We were told that you must run more than a quarter tank at all times to cool the pump properly. We think that he might have run it too low on gas (not much though, and I think it'* BS to expect to have a level like that all the time)

I bought a new fuel pump, and the relay as well. Can anyone give me the exact location of this relay? I was under the pass side of the dash, and saw 2 identical numbered relays to this. I tried pulling the relay & it started with either removed. I am thinking it was a headlight, A/C, Horn, or some other relay that I was pulling. Is it possible to start it without the relay? I would really appreciate your help with that.

I think we are going to change out the pump just to rule it out. If the wiring got hot, that could be our intermittant problem.

Has anyone ever converted to an MSD or aftermarket fuel pump? I would like to eliminate/bypass the stock one, rather than change it every 8 months. Again, there are plenty of fuel pumps out there that don't have to be in a half tank of gas to run.

I know Nate has learned a lot from this group! We enjoy working on it together.
Thanks in advance.

John Christensen http://home.comcast.net/~johncgg/elcamino.htm
Nate Christensen http://home.comcast.net/~sk8nate/bonneville.htm

The Relay is located on the right hand side as you had first thought. Here is a pic for clarity.



Remove the fuel pump relay (2) from the right half Instrument Panel Power Distribution Center (1).

You may want to look at http://www.zzperformance.com/zzp/pro...rewire_kit.htm for a rewire kit and http://www.zzperformance.com/zzp/pro..._fuel_pump.htm for a new high flow fuel pump.

This is EXACTLY what I needed. Makes me want to go out and buy a Pontiac for myself, with such a great support group!

I am going to try the relay this morning, and make sure that it'* running with just the relay swap. Then open the larger can of worms, and look at the pump and wires. If they are iffy at all, I will change the pump.

The rewire kit looks like a good idea. In fact, If the relay is the problem, it might be a better idea to wait on the tank removal, till I can rewire the pump at the same time. With motors, they can actually create more heat if they are under supplied.

Thanks!
John

Also dont forget the fuel filter. If its bunged up the pump will kill itself trying to push through all the crap?
Electric motors are my life (industrial electrician) and your correct in stating that if the wire is too small (voltage drop) that the current will go up and create heat, which reduces the life of the motor. Rule of thumb every 10*c increase in temp equals half the life of the motor (electric).

I will be changing the filter too.

Nate just took a break for lunch, and it died again. He got it started, and drove it home to get a different car till we change the pump, with the new wires.

Is there an External pump that would work for this? Can the pump be bypassed, or will the pump itself impede the flow if it'* there, but not pumping?

Thanks,
John

Sure it'* the pump, and not something else like the Fuel Pressure Regulator?

Pretty sure it'* not the regulator, because the pump does not make a sound when the problem occurs. Usually the pump turns on with the key for a bit. It was not making a sound when the problem happens.

I will share with you another angle that a friend of mine on the El camino List sent me, along with my responses. He'* got a lot of GM experience: It may help someone here down the road.

Thanks Guys!
John

>>>>>>>>>>>>>>>>>>>>>>>>>>>>
>
> >I am about to put in another new fuel pump on the 4th of July. In December
> >(Sub Zero here in the Chicago area) The 1996 Bonneville SLE stranded my
> >son Nate several times, before getting it towed to a local dealer. $700
> >later, it had a new fuel pump and sending unit. Last night, it stranded
> >him again.
>
> Ouch. Someone I know just paid $300 to a bubba joe bob brain
> (anamaniacs) shop in the sticks to change a pump in a 91 burb and it has
> died twice since. That'* allot for a $50 pump and a half hour work.
>

I am hoping it'* only an hour or so. Was that one inside the gas tank too? I lowered the tank on the Elky one time and it took me a lot longer than a half hour. Then, I suppose it would take you more than 5 or 10 minutes to size a ring <G>

> >It was too cold to get under there ourselves last winter, but "poor people
> >have poor ways", and we have to do it ourselves. It started today after we
> >had it towed home, every time, all day, but I don't think it can be
> >counted on. We were told that you must run more than a quarter tank at all
> >times to cool the pump properly. We think that he might have run it too
> >low on gas (not much though, and I think it'* BS to expect to have a level
> >like that all the time)
>
> >
> I'm not sure where it is on the bonne. On most cars it'* behind the
> dash on a box located on the passenger side at the lowest and furthest out
> part of the dash. It may be in the engine compartment under that big
> plastic cover with all the fuses. It may be in the owners manual in the
> fuse box section.
>

I got the location for the pump relay from the Bonneville Club Guys & changed it.

> >I think we are going to change out the pump just to rule it out. If the
> >wiring got hot, that could be our intermittent problem.
>
> Could be a bad pump. Allot of the replacements are cheap. Walbro
> makes a good pump.
>
>

Nate just took a break for lunch, and it died again. He got it started, and drove it home to get a different car till we change the pump, with the new heavier wires. I think I will go with the Walbro pump, for only $6 more than I paid for the Delco, and take the Delco back tomorrow.


Is the bonne a supercharged 3.8. They are a little different. They
> have a module that runs the pump at lower speed during most times then
> kicks it to full speed when extra fuel is needed.
>
>

No Supercharger. I had a 1992 SSEi for about 8 months, but could not justify 15 mpg in a car that should do better. I would NEVER think of hitting the pedal just to make the Boost gauge go up.....

> >Has anyone ever converted to an MSD or aftermarket fuel pump? I would like
> >to eliminate/bypass the stock one, rather than change it every 8 months.
>
> I don't know how you would bypass it. The pump would still be in the
> tank. The external pumps are pure junk cause they run hot because they are
> not in the fuel. I know guys running them and they only get a few months
> out of them.
>

I will rule this out then.
>
> With the engine cold. Hook a volt meter to the pump power wire,
> usually purple. Have someone just turn the key on and see if there is
> voltage there. It should have power for ~2 seconds then stop. If it does
> it'* working right.
> Now try starting it and see if there is power there. If working right
> it should have power.
>

You can hear the pump for a few seconds when you turn the key on. The night he had trouble, he had someone under the car to listen, and it was not running. I think you hit the nail on the head with the communicator pad theory.

> These tests can be done with the wiring hooked up.
>
>
> It sounds like you have a pump with a bad commutator pad. When it
> stops in that spot the pump won't get running again cause it causes an
> open. Sometimes the tow back is enough to vibrate it so the brush hits a
> good spot and the problem goes away for a while.
> An oscilloscope with an amp clamp will verify a weak/dying pump bad
> commutator in seconds. Just look for an irregular spike. It'll stick out
> from the rest. You can also figure out the rpm of the motor by counting the
> spikes. that helps in diagnosis as well.
> Also check the average amp draw of the pump. As a pump dies the amp
> draw will go down.
>
>
> Since you have had the same prob before and the pump was replaced
> I'm assuming the pump is bad. I seriously doubt you problem is due to
> running low on fuel unless it'* always driven on 1/4 tank or less IE only
> putting $5 of gas in instead of filling it up. ( I have never understood
> that) Also since you live in a cool climate your tank/fuel stays much
> cooler than it does here in the summer and you are not capable of running
> the fuel hot enough to harm the pump. (it does take allot of time running
> at low tank levels and high air temps to burn one out).
>
> Since you had the pump replaced at the dealer it should be a Delco
> one. I have had allot of probs with Delco electric parts lately. Some of it
> is Ok some just doesn't last. I have had good luck with Master fuel pumps
> and better luck with Tomco but they are very hard to find.
> I'm not a big fan of some of Borg Warners parts.
>
> Robert Adams
> http://gparts.freeyellow.com

I think I may have a similar problem to yours also with a new pump. Last october the car would randomly die or not start, sometimes jumping it would help (weird) to get it started again. Finally it just wouldn't even try to start. Towed it to the dealer, and two days later had a new pump and upper intake (thanks dad!). Well, it dying periodically again, usually it'll start again in a minute or so. No real warning, revs just drop way down, and the engine coughs and sputters at 200 rpm or so up to 1000 then dies. Once I was staring at the gauges waiting for it to die (optimistically I might add) and the volt meter showed a drop to the 10 or 11 volt range, then she died. Similar things occured with the last blown pump. Anyway, the car doesn't like the AC being on and the stereo turned up (two big amplifiers in the trunk pull a few amps and drop the current noticably at times) so I can get around with the windows down and the radio off for awhile if I don't have to sit and idle much. I'm just checking if my symptoms are indicative of another bad pump... grrrr.

Check the connector!!
I found this today,
Sorry i cant post the pics on this one, but the connector looses it compression when heated and open up casuing a failure, when the pump cools down the connection is made again, have a good look and use a pick to close the tabs together a little tighter

I'll check this tonight. I ordered the Walbro pump, wiring harness, and Alternator cable. I'll be replacing the fuel filter too.

I am assuming it'* the connector right at the corner of the tank, between the body & the tank. Looks like a 4 wire if memory serves.

Thanks!
John