P0171 Nissan -

Question

Hello,

I have a 99' Nissan Altima. I am running this code. Sometimes the check engine light turns off by itself ( then back on obviously.)
The car sometimes has a slight rough idol. There is really no hesitation and the car's performance isn't really a problem.

The knock sensor is also coded, but I think that is because of the 171 code.
I clicked the MAF sensor so it isn't that.
I also used fuel injector solven cleaner. I used techron, heard that one is the best.

Don't know if I should get the injectors smoked, or if it another problem? I just don't want this to be a larger problem in the future... and advice appreciated.

Thanks!

Answer 1

the knock sensor code is on due to P0171. 

disconnect the battery for 30min or so to reset the ECU. you can do it with key sequence but its a little hard.

I would also clean the mass air flow sensor with mass air flow sensor cleaner