Hey everyone maybe you guys can answer my question since no one else can. I recently started to have a really bad knocking when going uphill. Doesn't do it at all when going downhill or on flat ground. Any ideas?

 

bump

 

The first thing that comes to my mind is a lean air fuel mixture. That will cause the check engine light to come on and produce codes PO171 and/or PO174. There are a number of causes for the mixture to become lean. Vacuum leaks, a stopped up fuel filter, and bad ful are only a few.

I could be way off base here, though. If the Check Engine light is on, posting the codes here will help.

 

ill see if I can get it to the auto parts store to run the codes. the last time i did codes it came up with o2 sensor and/or egr valve the guy said both things throw the same code.. dont know if that true or not