I got a a P0420 due to a dirty MAF. Had some know it all on here claim the MAF never causes a P0420. I gave the MAF a good cleaning and...poof: no code. It just took a cleaning. Have you ever cleaned yours?
Yes I have an oiled air filter so I clean it 1-2 times a year just in case. I do not notice any difference in the before/after fuel trims so I may be overdoing it but I'm ok with that.
Yes I have an oiled air filter so I clean it 1-2 times a year just in case. I do not notice any difference in the before/after fuel trims so I may be overdoing it but I'm ok with that.
OOPS. I know I quoted you, but that last question was meant for the OP in this thread. I clean mine when I do my plugs at 30-40k, but that one time I was late on both. That's why I did the MAF in response to the P0420. The sensors were not old and I had checked the exhaust from stem to stern.
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'99 4Runner SR5 5spd 3.4L V6 4WD(U.S), original '99 Talls in front, OME 906s in back, Hella fogs, Trekmaster shocks in front, Billy in back, no running boards, FIAMM horns, Alpine sound, Michelin LTX M/S2's, owned since new.
'97 HiLux SW4 5spd 4WD(Japan model bought in Brazil assembled in Argentina, very close to a 3.0 4Runner/Surf)
'71 FordWillys Jeep CJ5 (with straight six Ford Maverick 3.0 liter engine--lives in the mountains north of Sao Paulo Brazil) My Backyard Frame Swap
My corolla always got this code in obd scanner i examined several times, checked o2 sensors, battery cables, exaust but i found easy way to clear p0420 code is do is replacing the catalytic convertor with the new one.