P0171 code

Question

I have a IS300 2001 with a P0171 code. MAF was dirty cleaned it with great improvement but it still went to P0171 code after 100+ miles of driving with a very little hesitation on mid acceleration.

Answer 1

Hi there,

Sometimes cleaning is not enough with the maf sensor, however the front O2 sensor can also cause a lean fuel mixture and code. Without a scan tool it's difficult to determine which of these sensors is causing the issue. I would suggest also looking for any exhaust leaks or possible issues with intake leaks. It sounds like the issue may be the front O2 sensor since the vehicle is running decent.