Rpm Surges At Idle, Check Engine Light W Codes, HELP!!!

[ariston18]

Hi everybody I'm new in this forum.

I just bought a 2001 Volvo S40. The RPM surges when its at idle, and sometimes it even stalls when its set to park. It had a Check Engine light so upon downloading the codes at the auto shop, they told me I had P0101, P0102, which points to the mass air flow, and P0450 which points to low fan circuit. I'm not sure what it all meant, but basically they said I need a new MAF sensor, and that should clear the fault codes and the stalling at idle problem.

I got a new MAF sensor and installed it. Went to Autozone immediately, cleared the faults, but the engine still rough idles. The check engine light came back on again on the same day, and I still have P0101. I've only changed out the MAF sensor for a day. Do i need to "break in" the part? As in drive the car for a few days first, then go and clear the code? Or could there be another problem?

I've read up a little bit and some recommended cleaning the throttle body and air intake valve. Im not much of a car expert, but yet too cheap to pay a dealer, so can anybody tell me how to do it? Best if there's a link to pics on how to remove and clean the throttle body.

Thanks for reading!!!