Mas Air Flow Sensor

**Sonicgth** · 09-19-2012 04:18 PM

I suspect my MAS is going bad, checked the code and is either a MAS going bad or a vacuum leak. I cleaned the MAS properly and the check engine light went away. After two days it is back on. Does the car need the MAS to run properly. I disconnected the electrical plug and it seemed to idle better and was very responsive. Any hints on how to isolate a vacuum leak?

**natepless** · 09-19-2012 07:52 PM

How To Find A Vacuum Leak - EricTheCarGuy - YouTube

But like the guy says there is a small chance it could ignite.

**Sinister** · 09-19-2012 08:51 PM

don't do that.

A smoke machine is a better idea.

What part of the country do you live in sonic?

**impretzel** · 09-20-2012 03:13 AM

Originally Posted by Sinister

A smoke machine is a better idea.

^this

Do you have a volt meter? You test for a bad MAF by probing power and signal wires on the back of the plug and see if the volts are in spec. Maybe a more knowledgable member can help with the volt spec?

But yes, the maf is required for optimal performance, fuel consumption, and cleaner emissions. Im surprised you got better results with it unplugged lol.

***mycologist*** · 09-20-2012 04:26 AM

Post the codes.

Check all the clamps on the intake track especially between the MAF and the turbo. Make sure there are no tears in the inlet. Make sure all the return lines to the inlet ar attached and tight (I used zip ties). Make sure the intake box is fully and properly closed - those two tabs on the bottom have to be in good.

Your MAF may be disagreeing with your front O2 sensor, and the O2 sensor may be the problem. The fact it got better with a cleaning is telling but I can't see how it would get re-fouled in a couple of days unless you are running some oily air filter.

**Sonicgth** · 09-20-2012 06:48 PM

I live in St. Louis. The smoke check is a great idea. I will also try all the other suggestions as well. It looks like there could be a little tear in the boot or hose connected to the turbo. I will have to disconnect the clamp to inspect.