Q: P0171 and P0442 in a 2003 VW Jetta 1.8T. We bought it used 144k miles. Light came on before changing the air filter. Any solutions

asked by on July 03, 2017

Bought the Jetta used at a good price. On the way to work the engine light came on got it checked out and said P0171 and P0442 EVAP codes, keep in mind this has happened before the air filter was replaced since i didn't know if the original owner has ever replaced it. So it says to most likely to replace the MAF but i dont know of to put down the money yet on a new part. Also as they were replacing the air filter they noticed there was huge handfuls of dust or dirt stuck in the filter so who knows if that has anything to do with this problem.

My car has 144540 miles.
My car has an automatic transmission.

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Hi there. The two codes you’ve listed might indicate different problems than you’ve been told are the root source. The P0171 code means that, on the first bank of the engine, the fuel system is running weak or a vacuum leak exists near this side of the engine. A lean condition occurs when the engine either receives too little fuel or too much air. P0442 is present in vehicles that have a small leak in the EVAP system. Some of the causes of the EVAP code include a faulty or loose fuel cap, EVAP system line leak, charcoal canister leak, a fuel tank leak, or perhaps a failed vent or purge valve. The mass air flow sensor might be the right replacement for the first code, but there are other possible sources. It might be best to have a professional mechanic complete a check engine light inspection, so they can isolate the source of these codes and recommend the right repairs.

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