Just when I thought things were going good...

I've been dumping money into my 99 about every week to keep her running smooth instead of spending the cash on a new car payment. It has been running great, but all the sudden, my SES light came on again. It happened as soon as I drove about 200 miles and fueled up. Gas cap is on tight. I've noticed the fuel pump is whining a bit more than usual. I replaced it about 4-5 years ago. It still seems to be running same as before, except the idle is a tad rougher than before. Could my fuel pump be going out again? Would it be trying a new fuel filter? I know the light means about 1000 different things, but thought a little insight could help until I can get it checked out.

You need to get the code (or codes) read before we can help you. Most Autozones will do it for free.

//2000CAYukon

Actually just ordered a cp9125 handheld code reader off ebay this morning. Will be here in a few days. Figured it was a wise $40 investment seeing this isn't the first time a code has, or will pop up. Will let you know what code it shows. Thanks!!

The two times that my fuel pump went my light never came on. I would say since its running a little rough your MAF or you may have a bad plug without the code info. You can usually go to Kragens as well to get the code read they don't usually charge. A code reader is great to have though it has saved me much money.

It threw a P0420 code - Catalyst Below Efficiency Bank One. From what I've gathered and read, this means a bad cat...most likely. I reset the computer and it is yet to pop on again. We will see what the future holds. That will be my first repair, then o2 sensors if it still isn't working. Since I have 165k on it, probably time to replace them anyway.