Ever since I did maintenance on my 2000 Limited I've had an intermittent check engine light. Took it to Autozone and they pulled a code P0171. I thought I had damaged the MAF sensor when I cleaned it, and had planned on replacing it, but the 4Runner still ran great. I was getting ready to order the sensor today when I figured I better double check to make sure I can't see anything obvious. I pushed on my PCV valve to make sure it was secure and it broke like this:





Could this be the cause of the CEL?

 

It's possible...If the PCV valve was broken/cracked you should have had a high idle,because of the vacuum leak...If not..chances are good that the MAF needs to be cleaned/replaced to take care of the P0171 code/drivability.And that the PCV valve was just brittle(probably aftermarket) and broke when you tried to check it...replace the PCV valve gromet as well as the PCV valve..I bet its hard as a rock.

 

Ok, I'll replace them both. I don't recall a high idle, so that's probably not it. Though, even now that it's broken, it doesn't idle higher than it used to. Maybe it was idling higher the whole time and I never noticed it.

How do you replace the PCV valve gromet without it falling into the engine?

 

IIRC you can pull the VC...
Or without doing that your going to need some luck...

 

a mechanic of mine also suggested the p171 was a poor MAF function, but those errors are supposed to throw a p100 or 101