99 chevy silverado fuel & oil gauge needle surges

Hello,

My truck is a 99 silverado with the 4.3L V6 64,500mi

About a week ago the Service Engine Soon light came on in the truck. I took it down to auto zone where they hooked up the scanner and it revealed 2 codes, 450 and 451. They asked if I ever fueled the truck up with it running, to which I dont believe that I did... but anyway they said that maybe the gas cap was loose. I checked it, it was on good but tightened it anyway & they erased the codes for me.

The next day... I noticed that the fuel gauge didnt seem to be reading accuratly.... I had about a quarter tank in the truck... but when I started it up... it went up to three quarters.... then within about 5 minutes it slowly sank back down... It has been doing this sort of thing with varying fuel levels ever since then and also the needle has been surging.... like the needle will be sitting on half tank... then jump to full... then sink back to three quarters... then jump up a little bit... then sink down to half... etc.... The check engine light was not on yet again but it was doing this... Then yesterday the check engine light came back on.... fuel gauge still doing this.... and today driving home I noticed that the oil preassure gauge started doing this.... Usually it sits just a little above 40... but today it was moving between 35 and 40.... Then the low coolant indicator came on in the message center. When I got home... I checked the oil level which is fine (As always) and coolant level. This truck is taken care of... Oil & filter changed reguarly but I am concerned about this...

What can I do????? If there is any information that I left out or a better explination is desired on anything... please let me know as I know my way of explaining is not always completly understood by some :)

Thanks,

Keith

Reply to
GeeBeer
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Okay Okay... I am just paranoid LOL.

Coolant level was low... somehow, I filled it up and that message is gone. The fluctuations in the oil preassure gauge was because I noticed it when I was driving on my driveway (Long Long Long driveway) and going idle to touching throttle to idle was causing the different readings... So those two are fine.

The only thing that appears to be wrong is the deal with the fuel gauge. It is bouncing back and fourth and the check engine light is on. Maybe the fuel level sensor is going out? Maybe this going out is causing the 450 and 451 codes?

Reply to
GeeBeer

I really don't know about the codes... but my '00 S10's fuel sender started to crap out on me, and the fuel gauge was fluttering around like that....

I don't "think" it was a cheap fix - I traded the truck in shortly after.

-marc

Reply to
Marc Westerlind

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