Fuel pump thread ('91 High Output)

Hi everyone,

Thought I'd post up my ordeal to help others out.

Recently I purchased a '91 XJ. The fuel pump would start whining - usually after about 30–45min of driving. So I decided to change out the fuel pump this weekend. Turns out, the PO had installed an Airtex pump.

I first purchased the following:
Spectra Premium SP7091H Fuel Hanger Assembly with Pump and Sending Unit

Amazon 'confirmed' it fit a 1991 XJ.



Upon installation, the fuel gauge was reading opposite of normal. My fuel gauge increased the more fuel was spent. This is because Jeep reversed resistance in the sensor in 1991 as far as I can tell.



So I immediately pulled that pump assembly back out and went to O'reiley's. They sold me a fuel pump with assembly under the brand name "Precision". I brought it home, took a second look, and noticed there was another sticker hiding under the Precision sticker. Turns out, it was an Airtex on which they just slapped another label. Precision = Airtex. So back to the store that went and returned it.



Finally, I went to Advance Autoparts. They sold me a Carquest pump. Upon testing the float it read correctly on the dash.


No matter what I tried I couldn't get it to sit flush against the tank. I reached into the tank and pulled out an old grommet, but it still just did not sit right. Eventually i forced it into place and put a lock ring on. It is now weeping fuel a bit. I am hoping it will stop after some time, or I will have to pull it all back apart again.

Hope this helps someone in the future.

If anyone in Colorado needs a 1990 or earlier fuel pump, I have one that was only installed for a few hours.

Yep those big name store pumps are horrible, even NAPA. I've heard the advance ones are the same. They whine and the gas hand doesn't read correctly. I'm currently running a precision and it whines but it's been doing since the first week I installed it 3,000 miles ago. I've read that they can go on for years whining. You never really know. They are such garbage I just posted about this in another thread.

Ill post the same advice here.

1. Never, ever throw away your stock sending unit.

If you did throw it away. It's ok. Just go to a JY and get an original sending unit. Then order just the Bosch pump and install in to the stock sending unit. From my understanding that will solve the whine and gas hand problems.

Second piece of advice. CLEAN YOUR TANK. I don't care how much you think. "Ah it's fine." No, it's not. You see you probably put a me fuel filter on didn't you? Good.
But if you didn't clean the tank it will pump that dirt into your filter clogging up your new filter. Then your pump will burn out in 250-500 miles. You'll think it's a bad pump and trade it. Then it will burn it out again. At this pint you'll realize something's not right. So you'll run a new ground for your 3rd pump and check continuity then it will burn that one out too.

WTF? You never even thought about that new fuel filter from the first pump. So finally you realize I've to drop this tank. You look in and "hello" filth. You'll put 2 & 2 together and take off the 3 month old filter to find it's mud and weighs a ton. So it took 4 pumps and just weird circumstances for you to learn a dirt tank will F up your filter, in return F up your pumps. And at first you'll blame the crappy airtex (it is crap). Yes, it happened to me.

Sorry it's so long. I just don't anyone to ever go through that.

He didn't have the stock set up any more because the PO went aftermarket .

IMO all that aftermarket crap is built by the same factory in china. I've dealt with aftermarket pump and sender in one ours, ordered a junkyard pump and sender assembly and a new Bosch pump to go with it, for the long term it is the best solution . The aftermarket senders never read correctly in my experience. Still finding a good used fuel sender can be tricky for a 25 year old ride, thank god they were plentiful so the parts are still out there all these years later.

Use Bosch pumps only.

I had a rash of "new" pump failures on friends' Jeeps recently.

All the rest suck.

Yep.

I'm with Cruiser.

OEM sender. Bosch pump.

BALTANAKT said:

Yep.

I'm with Cruiser.

OEM sender. Bosch pump.

Click to expand...

Yessirree.

I've been through every aftermarket pump, at this point I try to find stock OEM pumps from low-mileage vehicles

Just changed an OEM one the other day. Had Jeep part number and Bosch part number on it.

Bosch made the OEM pumps, but made them to Jeep's specs. The current Bosch pumps that are on the market say "OE style" but are not the same pump

Maybe not the same, but still the best.

They come with adapters to accomadate the difference in size.

Bosch was building electric fuel pumps before Jeep had fuel injection.....

Yet I can carry an OEM without carrying a sack of spacers and wiring adapters

That's wonderful.......

If those things confuse you, I wouldn't carry them in the same box myself.

Google "contrarian" when you get a chance.

Don't know if its wonderful but it is better for sure. Hence why the stock pumps are the best. Got nothing to do with what you assumed, did it