99 Jimmy: 3 fuel pumps in 4 months

[britincanada]

Hi there ive got a gmc jimmy 1999 4.3ltr 4 door 4x4

ive had 3 fuel pumps in 4 months the story goes like this

I shut it off then tried to restart and it wouldn’t start .The engine was cranking over but didn’t seem to be getting fuel.

When we banged on the gas tank it started.

Number 1 fuel pumps installed.

Seem to be ok for 2 mth then same again

I shut it off then tried to restart and it wouldn’t start .The engine was cranking over but didn’t seem to be getting fuel.

When we banged on the gas tank it started


Number 2 fuel pumps installed and fuel pressure regulator, alternator and battery

Seem to be ok for 2 more mth then last night it did it again I drove 1 mile
Went for a beer came back

Tried to restart and it wouldn’t start .The engine was cranking over but didn’t seem to be getting fuel.

I called CAA tried to jump it no joy so he banged on the tank and it started

Number 3 fuel pumps installed today.

This is driving me nuts any idea what could be making the pumps fail
im thinking there’s an underlying cause to this but what

? am i going to be putin numer 4 in in 2 mth

All 3 pumps where acdelco pumps

The gas tank was cleaned out so no garbage in the tank
Any help would be good thanks britincanada

[Chris Stewart]

The fuel pump has to keep plenty of fuel going through it...fuel cools and lubes the fuel pump. Since you don't say the motor is running poorly,
I would suspect:
The tank being run out of gas too often.
The wiring connector to the pump not keeping a good connection.

[britincanada]

The motor runs very well when runing .
gets serviced at the right times.

and i fillup every time the gas light comes on so could that be the problem
i need to have at least a 1/4 tank of gas all the time

i allso live in winnipeg where the temp can be anywhere from plus 40 to -40

right now -32

[ericn1300]

Originally Posted by britincanada

i allso live in winnipeg where the temp can be anywhere from plus 40 to -40

right now -32

I hope that's not centigrade

if it happens again try cleaning out the gas tank, you might have contaminants shortening the life of the pump. also try adding a gas dryer or water removal treatment. if you routinley have less than half a tank of gas the other half is air and you may be getting water condensation out of the air from the cold weather.

[JaVeRo]

Two things come to mind.

First would be the ground. Make sure the ground wire is still attached. It is possible that the ground wire is broke or missing and the pump is grounding thru the mounts.

Second would be the plug. I had a suburban company truck that had 2 pumps installed in 3 months. When the second went out we pulled it to the dealer and it cranked right up. A few days later it failed to crank again so I dropped the tank myself and found that the plug had separated. There were two sets of ears on the plug, one to disconnect the plug from the pump and the other to separate the plug components to remove individual wires. Apparently the first mechanic reached above the tank feeling for the ears or tabs to disconnect and partially separated the plug instead. Or it could just be a bad plug.

James

[DelCoch]

If you bang on the tank and the pump runs, it doesn't sound like the pump is bad. When a fuel pump goes it's usually gone forever. (Did you check out any of the old pumps after they were replaced) Fuel pumps don't come and go, but a loose wire connection will. As has been said, I imagine you have a bad ground or a loose connection, either inside or outside the tank.

[MT-2500]

Originally Posted by britincanada

Hi there ive got a gmc jimmy 1999 4.3ltr 4 door 4x4

ive had 3 fuel pumps in 4 months the story goes like this

I shut it off then tried to restart and it wouldn’t start .The engine was cranking over but didn’t seem to be getting fuel.

When we banged on the gas tank it started.

Number 1 fuel pumps installed.

Seem to be ok for 2 mth then same again

I shut it off then tried to restart and it wouldn’t start .The engine was cranking over but didn’t seem to be getting fuel.

When we banged on the gas tank it started


Number 2 fuel pumps installed and fuel pressure regulator, alternator and battery

Seem to be ok for 2 more mth then last night it did it again I drove 1 mile
Went for a beer came back

Tried to restart and it wouldn’t start .The engine was cranking over but didn’t seem to be getting fuel.

I called CAA tried to jump it no joy so he banged on the tank and it started

Number 3 fuel pumps installed today.

This is driving me nuts any idea what could be making the pumps fail
im thinking there’s an underlying cause to this but what

? am i going to be putin numer 4 in in 2 mth

All 3 pumps where acdelco pumps

The gas tank was cleaned out so no garbage in the tank
Any help would be good thanks britincanada

All ways keep a 1/4 tank or more fuel in tank.

Was the pumps checked for being bad out or just replaced?
As said the wiring plug in can be a problem.
Always check things out before replacing.

[britincanada]

Thanks for the input i will look into all ideas

All wires and lines checked by garage

Tank cleaned out


I hope that's not centigrade yes it is -32c

All pumps checked at garage or should i say pressure tested before being changed and new fuel filter fitted

All pumps have been replaced under the 1 year pump warrantee and 90 day labor warrantee covered by garage.

So cost to me is nil just a big lack of faith in the jimmy every time I use it now
but i do like my jimmy

thanks Brit

[ericn1300]

could always be a bad production run on the fuel pumps the shop is using, you might try another brand. the parts supplier should only charge you for the difference in prices after this many returns.

[BlazerLT]

sounds liek there is somethign wrong with the sending unit and/or the wiring needs to be cleaned and reinstalled.

Is the grounds ok?

[muddog321]

Check this out on the connectors:

http://www.airtexproducts.com/pdf/GM...0Harnesses.pdf

[JaVeRo]

Originally Posted by ericn1300

I hope that's not centigrade

-32c = -25.6f you have to keep in mind that 0 deg. centigrade is the freezing point and 0 deg. fahrenheit is 32 degrees below freezing. Sorry I just couldn't resist. Either way, it's colder than I ever care to see.

James

[J-Mech]

GM put out a service bullitin on the blazers. The connector at the tank should be replaced because the oem one had a defect. The updated one is available. About $15. Replace no matter what the old one looks like.