99 Tahoe intermittent loss of power, P0131 & P0151, dancing fuel gauge

[niik]

Hello everyone.

I just bought a '99 2-door Tahoe with 127K on it, and decided to take it to the desert yesterday to try it out.

Towards the end of the drive and when I was about to climb a big dune, it felt like it had not much power left.
I shifted into 4LO to see if it would make a difference but it did not.

After reflating the tyres, everything seemed to be fine and I decided to give it gas for about 20secs, and in return, I got some nice acceleration on the highway.
A minute or so later, I tried again, and this time, I got what I had a couple days back, that is virtually no increase in speed, and the SES light went out.
The car gradually lost all power on the way back home, and in the last kils or so it felt like it was out of fuel (but wasnt).
I started the car this morning to check the codes, and after a little bit of hesitation it started fine, but I feel that the idle is a bit rough.

The codes are for the O2 sensors, and I felt that this could be because the car was running lean when accelerating.
I cleared the codes, went for a drive, pushed the gas on a couple of occasions, and the SES light did not come back, it was driving fine, still a bit rough at idling (630-650 rpms)

The guy who sold me the car told me that the fuel pump was probably on its way out.
The shops are closed today, but I was thinking of getting a fuel pressure gauge tomorrow to check if I am getting the 58+ PSI I should.

Everything to me points at a dying fuel pump which fails after prolonged use.

What do you guys think?

 

[justimagination]

Your vehicle definately needs a fuel pump, also the fuel gauge float is part of the pump as well.
I would recommend AC Delco part only, also change in line filter as well. Good luck............about $500.00 by certified mechanic which carries 12/12 warranty.
david g.

 

[btowns]

For surely sounds like a fuel pump issue, but if for some reason that doesn't fix it, it could be your cats. I had a similar power issue in my 97' Yukon (similar build) and turned out to be a clogged cat. just cut it off and ran with my magnaflow muffler, everything went back to normal and it sounded great. Just a tad more insight for you!

 

[niik]

Thank you for your inputs. :happy160:

Actually, my mechanic mentioned exactly the same thing about the cats, but it was not related (at the time) to the current issues I am experiencing.

Definitely on my 'to do' list :naughty:

Nik

 

[lesterl]

Nice truck dude, I picked up an Delphi OEM pump for my 95 off AMAZON.COM for $100 or so...... Great place to buy parts from and I would NOT use an Aftermarket pump... GO OEM....

 

[niik]

Nice truck dude, I picked up an Delphi OEM pump for my 95 off AMAZON.COM for $100 or so...... Great place to buy parts from and I would NOT use an Aftermarket pump... GO OEM....

Thanks. I found one on ebay for $160 (amazon was $222), which I will get from the US so much cheaper than getting it here.

Upon inspection, the trunk has already an access point for the fuel pump :waytogo: Something tells me that this truck is not on its first pump...

Anyway, today I replaced the fuel filter to start with, and it was very very clogged up and heavy. Its night and day with the new one on!

The tahoe jumps and gets the acceleration that I never thought was there.

I will keep you posted on my progress.

Nik

 

[lesterl]

xxxxxFingers Crossedxxxxx

 

[niik]

xxxxxFingers Crossedxxxxx

... only lasted a week or so.

I am definitely changing the fuel pump, as I identified that it really does seem to 'heat up' on long trips (let's say driving for an hour or more), resulting in zero acceleration towards the end of the trip.
I had thought that refuelling mid-trip may have helped solving the issue by cooling it down a bit but it didn't.

So I ordered this Delphi OEM one from Ebay, and will keep you posted when it arrives.

 

[Jounier11]

Wow! what a coincident i actually had this problem recently too replaced the fuel pump and filter all turned out good.

 

[niik]

Wow! what a coincident i actually had this problem recently too replaced the fuel pump and filter all turned out good.

Well thanks for that, it is quite reassuring 'cause there are many other things that can cause a similar issue like injectors, distributor etc.

I am still driving the car every day waiting for the pump to arrive; the car is more and more difficult to start, has less and less power, and the transmission seems to get confused at times.

This is my first Tahoe, and when I got it I thought that this was the acceleration I would always get, until I changed the fuel filter, and wow!

Back to the acceleration of a hamster pushing a filing cabinet for the moment though.

 

[Jounier11]

yea but if it were to be an injector you would smell alot of gas in the cabin like my 96 tahoe (which had f***ed up injectors) would do!