Hello everybody,

2000 4Runner, SR5, 3.4 Auto, non-cali.

I've read all of the p0171 threads, but am still a little stumped.

So far I have done the following:

Cleaned the MAF (with proper cleaner)
Cleaned TB
Changed fuel filter
Checked 02 -Front and rear (checked resistance at ambient temp)
Checked MAF (checked resistance at ambient temp, varies with airflow)

The truck cranks about 5-6 times when starting, and idles rough when cold, hunting about 300 rpm.

When warm, it idles at a dead steady 700 rpm. This makes me think it's not a vacuum leak...

I'm not sure if it is down on power, the light came on reasonably soon after I bought it.

Any other checks before I pull the trigger and buy an O2 or MAF, or both?

Thanks for any suggestions, I want to get this problem behind me with winter rolling in.

-Drew

 

Is it throwing codes? Cleaning stuff does not always fix it. They say not to clean the air flow meter at all or it may never read right again but since it didn't change anything with you, your prolly fine. Sounds to me like a TPS issue or coolant temp prob. Have you resently done any cooling system work? Make sure its full of coolant and that you bleed the system of all air. TPS adjusted properly?