I am experiencing engine surging with my 2001 4Runner 3.4L V6. My check engine light came on and I took it to an auto shop to read the OBD II Code. I was told it was the Idle Air Control valve and may need to clean the throttle body. I had the light turned off and cleaned the throttle body. I made sure all connections were tightened.
Two weeks later the check engine light came back on. I drove it for about two weeks with the light on thinking it was the IAC valve error. I did notice some excelleration loss and engine surging/stuttering during excelleration. I took it back to the auto shop and a different error came up. I was told the MAF meter was the suspect and needed to be cleaned. Did that with computer air spray. Check engine light came back on and was then told to replace the MAF meter. I was also told that a random miss-fire showed in the code but was probably do to the MAF. Replaced the MAF meter, had light turned off. I was still receiving engine surging/stuttering during excelleration and the check engine light came back on. I don't have any loose vacuum hoses either. My engine as it stands is running lean and I'm having the surging/stuttering. I'm at a loss here and any help would be appreciated.

 

First off, clean the MAF with proper MAF cleaner; canned air won't help you much. Do you know what code you were getting? Sounds like P0505. Check out your throttle body first, then go from there. Good luck

 

You said the first time that you took it to the shop you were "told it was the idle air control valve and may need to clean the throttle body". Clean the IAC.

 

Thanks okie81 and brian2sun for the replies. I've replaced the MAF meter, so that's new. I was told that the IAC valve cannot be cleaned because in the 2001, it is built into the throttle body. I would have to replace the whole throttle body to replace the IAC valve. The original IAC valve OBD II error did not come up a second time when scanned regarding the check engin light. The surging is definitely worse and happens just as I start to excelerate. I'd like to avoid replacing my throttle body and find out it was something else. Do you think that the computer board still has the error or old MAF settings loaded even though that I replaced the MAF meter?

 

Didn't know that about the '01's IAC. Maybe you could have the shop test the TPS.

 

what was the code? that'd help out a ton.