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post #8 of (permalink) Old 06-22-2018 Thread Starter
Khenji's Avatar
Joined: Nov 2016
Posts: 6
Originally Posted by wmburns View Post
Originally Posted by Khenji View Post
just got some quotes from exhaust shops to see how much to fix the o2's, just having a hard time believing that the o2 sensors would cause it to drive rough like that
Do you want PROOF that the problem is related to O2 sensors? If so, you will need an ODB2 scanner capable of monitoring operational PID's. Look at the Long Term Fuel Trims (LTFT) for bank 1 and 2. IF there is an exhaust leak, THEN the O2 sensors will "think" that AF mixture is LEAN and will add fuel (positive LTFT's). However the AF mixture is likely OK. The additional fuel will make the AF mixture in fact RICH.

Sooooooooooo the next step is to examine the spark plugs to see if in fact the combustion has been RICH.

Then you will know for certain one way or the other.

Here's some information on an affordable Windows based ODB2 scanner with graphing capabilities.

ForScan ODB2 scanner w ELM327 USB
oh yea you sent that on the other forum that thing does like very helpful, but what you said makes sense. So it sounds like the best bet is to check for exhaust leaks and replace the o2 sensors? Should I replace all 4 or just the upstream on bank 1 since the code only referred to bank 1? Should I go ahead and replace the cats too?
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