The light just came back on again same code P0171. What to do next ?

 

George list off what you have had done... ALL of it... It will help others if they know...

 

Ok this is since I bought it:

1- Changed radiator as it was leaking (no overheat AT ALL after 4 hrs drive just low on coolant)

2- Had a rough idling and occasional stalling so I cleaned the TBD and MAF. Also cleaned the Air filter with the appropriate oil kit.

3- Spark plugs were changed (twice as the mechanic put a cheap ones so had to put other ones after a misfire in the engine). At the time, I took it to the dealership for a diagnosis, and they found out that the spark plugs failed but NOTHING else.

4- 3 weeks after cleaning the oil filter I had the P0171 code and the mechanic found that the MAF was dirty from the filter oil and cleaned it. He said the engine light will turn off in few days and it did. However today the same code came up again.

5- I did an oil change last week on it too.


the car is 07, and has 51k on it.

 

i put a $14 advance auto air filter in my 07. when it had 51k on it. thats when my mpg went up 1-2 mpg. id invest 14 bucks and try it for a week.
oh that wus a plain paper filter,nice and dry,no complications,just like stock. work every time. no f ups

 

So r u saying replacing an air filter regularly is better than cleaning up a K&n filter?

 

btw I have to add that before the engine light came up, a few hours before it did , I got SERVICE TPM on the board for a minute then disappeared. Since this is related to my tires (which I think I need to change them soon), I totally ignored it. But at this point I want to share everything as I have no clue why this is happening

 

so @drtom u r suggesting that I take off the K&N and replace it with a $14 filter, clean the MAF sensor and the mess done by the oil in the filter tube and drive it till the engine light goes off?

do you think that will do it?

Thanks guys

 

On most stock motors, including the Hummer inlines, the factory style paper filter will provide more airflow to the intake than the motor can feasibly use in all operating conditions except for complete wide open throttle and even at WOT the difference is minimal. Any additonal airflow provided by an aftermarket filter is simply not needed or utilized under normal operating conditions.
When folks swear they 'feel' an increase in power with K&N, it is just a placebo effect often due to the motor sounding different.

It has been proven that K&N filters allow more dirt into the intake system than a paper filter. A bit of research will result in a ton of info on the subject, including oil analysis done comparing paper vs. oiled filters which reveals significantly increased contamination of oil when using a filter such as K&N.

Yes, it is possible that if your filter was over-oiled, it could continue to re-contaminate the MAF sensor.

Also, that code could indicate a vacuum leak downstream from the MAF. Make sure the intake tube fittings and clamps are all sealed tightly.

 

will do and will report back here.

thanks a lot

 

ok so as I was driving to Autozone on my lunch break the light came off lol

so should I still do the cleaning? could the MAF get damaged if it keeps getting contaminated? or should I just keep it as it is and wait?

thanks