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post #19 of (permalink) Old 11-10-2019, 04:54 PM
Join Date: Nov 2018
Location: Iowa City, IA
Posts: 262
Originally Posted by Rotwiler View Post
Cleaned maf with electrical cleaner too. So far been 3 days driving and no cel light. I also looked at my torque app and my 02 sensors would fluctuate alot at idle, now both 02s are almost identical numbers, like. .8 and other will fluctuate from .8 to .7 and back, before would go +15 and to neg etc. Also noticed after starting cold, before would get a misc rough idle that lasted a second but lights, now idles smooth. Had me worried, but think it's good. Cost less than a dealer diagnosis to fix and took around a hour to do everything. I put in cheap $11 each vvt sensor things just to try to see if it could be issue, if pops code I saved old oem ones and put tools in glove box since only takes 5 minutes to replace them.
Your 02 sensor #1 should fluctuate from .1v to .8v every few seconds once in closed loop (engine control). The ECM is adjusting fuel delivery to maintain the optimal fuel/air ratio and uses the sensor reading. Sensor 2, after the CAT reflects the performance of the CAT and should not fluctuate that much. Mine stays between .65v and .75v, occasionly reaches .8 depending on engine load. High voltage indicates rich condition and low indicates a lean condition.
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