I think it's something with air intake because someone else made a thread about it and fukn answered then as a joke I was like "lol that's ironic 420 and it's about air intake" but yeah po135 is pre cat and po235 is post cat o2 sensor...I think. Lol I'm kinda sure but yeah. Not saying it is then I'm wrong but I'm 99% sure
Rise Above Hate | RELENTLESS
2000 Volkswagen Jetta MK4 2.0 GLS 5 Speed | TyTyVDUB
Magnaflow Cat-back Exhaust system, Raceland coilover springs, Boser hood, Short Ram air intake, Driver side Raxle.
1994 Ford Ranger Sport 3.0 4x4 Automatic | TyTy4x4
Magnaflow Duel exit Exhaust, Cooper STT 31x10.5-15 Tires.
I have this code (P0420) as well. I believe this code indicates that its the catalytic converter working at below efficiency. This might make sense as the car has 115,000 miles and I had a series of bad ignition coils that caused misfires that could very well have degraded the catalytic converter.
However, it could be the O2 sensor - so how do I figure out whether or not its the sensor or the converter?
A new catalytic converter from VW is $1010.00, which is outrageous to say the least. My question is this: What about third party catalytic converters? Why are they so cheap, and will they work?
The cost to fix this vs staring at a check engine light is ridiculous. A new catalytic converter from the stealership is, as stated, over $1000. The "test pipe" I had installed? $25. The two O2 sensors I replaced? $250 total.
2001 Golf GL 2.0L 5-speed
Monster truckin' at 26.5" Front and 27" Rear.
My cel just came on yesterday and it is the 0420 code. I cleared it with the scanner and it hasn't come back on. I don't suppose there is a way to check a cat to see if its flowing & working properly so judging by the 95k miles its probably that? My friend has a Mercedes w/120k and the cat was restricting to the point the car ran rough. We "took care of the problem" and now it runs great, what do you know?
2002 Jetta 1.8T Auto Trans
O2 Sensor Spacer im running one of these on an after market cat. cat was new and threw the code i now the o2 sensor was good because i had replaced it prier to me owning the golf. threw the 42 dd o2 spacer on problem solved. i had picked the spacer up locally so i only paid $40. for it.
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