So two days ago after a spirited drive I pulled up to a stop light after exiting the freeway and the engine cut off. Got all the lights on like the you would turning the key prior to starting. Put it in park, and it fired right up. Ran great the rest of the way home. I've got 42k miles on the car and it's never done that before.

Today, I stop at a light and get the check engine light and the "visit workshop" message. Car continues to run great. like there's nothing wrong.

So I got home and hooked the the iCarSoft and got the following:
P1081 - Air mass ahead of throttle valve, partial load
P1094 - Air mass ahead of throttle valve, implausible

I've been trying to research and did find one person with a similar issue of the engine stalling and said he heard it's one symptom of a failing MAF.

Do the codes above substantiate this? Does it seem like it could be the MAF?
I did clear the codes and went for another drive. So far, the codes haven't come back, but it hasn't been that long either.

I also read some talk about the oil fill cap and leaking, so I checked it. I believe it wasn't quite tightened all the way. It seems to have that "click" at the end, and it may not have been "clicked". Maybe that has no bearing, but just throwing it out there.

I appreciate any advice on this.

Thanks!
Vince

 

Pull it. 1-10 on difficulty its a 1

Buy MAF cleaner

Clean and reinstall

Be sure to clear code with code reader'

if no code reader disconnect battery for 5-10 minutes and reconnect should clear code

if not go to autozone and they will for free at most stores

 

the only thing tricky about the MAF is it is held on by security torx. Make sure to pick up one of these sets. Harbor freight sells them too.

 

Update:
After clearing the codes I went and bought some MAF cleaner. Taking out the MAF was easy (my 997.2 didn't have security torx screws). Unplugging the wiring connector not so easy, but figured it out after a few minutes.
Got it cleaned and put back together and went on one drive. So far no more check engine light.
I'll update again if this turns out not to be the fix.

Thanks

 

Resurrecting this thread...similar situation although engine didn't die. Got the CEL, had shop scan it and codes are:
P1081: Air mass ahead of throttle valve, partial load
P1094: Air mass ahead of throttle valve, implausible
P1079: AIr mass ahead of throttle valve, idle
I ordered and replaced the MAF 2 weeks ago. Connector looked to be in good shape without corrosion.

Now, CEL is back, with codes as above. Any thoughts?

 

Assume you’ve checked the obvious- any air leaks in the intake path, AOS, oil in the area near the MAF? You don’t use any oiled filters do you? How bout the condition of the wire that leads to the MAF plug?

 

Thanks for the reply Rich. Filters are standard OE. Intake boot appears to be in good shape without cracking or tears. MAF cable also appears to be in good shape. I do not see any oil leaks but have not yet checked the AOS. Think that’s the next thing?

Thanks
Evan

 

No problem...hard to say though Evan. Believe it or not, those codes can also point to other stuff like a clogged catalytic converter even. Not sure if this is a situation where you might need to take it to your Indy or Dealer to further diagnose. Good luck and let us know what it turns out to be.

 

Will do - plan to take to indy next week and will update

 

Just to update - finally got the car to my Indy 2 weeks ago. CEL never came back after 600 miles of driving since clearing codes after MAF replaced...fingers crossed, it stays that way. Should something change, I'll post again. Cheers.

 

Update: CEL has come on/offf several times over past month. Eventually the light came on and stayed on. At that point I dropped it at my indy. They replaced MAF again, light came back on 60 miles later. Same codes as above, now l with additional code for cat on bank 2...indy is scratching their heads on this somewhat. Apparently already tested for intake leak...

 

Apparently MAF cable in good shape. Looking into O2 sensors pre and post cat; if those don't improve it, possible cat replacement...as always appreciate any insight

 

2009 C2S 177K miles

Did you clean the throttle body? How is your idle... steady or bouncy? To clean the throttle body, remove the filter housing and hose from the throttle body, spray the crap out of the butterfly... pull it open with your finger, and spray like crazy again... jam a rag in there and wipe.

Peace
Bruce in Philly (now Atlanta)

 

Thanks Bruce. Idle is a bit bouncy, yes. I haven’t cleaned it but it’s a good thought. Is there a certain cleaner you recommend?

Thanks

 

Your MAF spray is perfect. Shoot the crap out of it. I am not saying this will fix your issue, but it is something you should do to clear the deck of a simple common issue with our cars.

Peace
Bruce in Philly (now Atlanta)