I started my car today and it was running rough, engine light came on. Shut it down restarted and ran fine. Checked codes PO172 and PO175 bank 1 and bank 2. Cleared codes and it seems to be running fine. About a month ago car started then died but haven’t had any issues till now. Mass air flow sensor ?

 

Cleaned the sensor all seams to be good. Maybe just order a new one to be on the safe side.

 

If you have an OBDII scanner with live data. You can just monitor what the MAF is doing at idle, and on load. Also if it has freeze frame data best to look at what the data looks like first.

 

It does have live data. I’ll watch it, And look back on some old posts what the values should be.
I panicked when the light came on. Last and first time was due to a valve spring failure causing the motor to blow.

 

The "started, then died" comment sounds like what happens right after you have the battery disconnected for a little bit. It does this normally upon the FIRST re-start after the "reset" (aka, having the battery disconnected).

Have you messed with the MAF or the intake recently? Perhaps a slight leak somewhere where something wasn't fully tightened...perhaps the tube onto the TB?

 

No changes for months. I cut the air box about 2 months ago and it’s been fine since. Our temps here dropped about 20 deg since last time I dove it which was only a day before.
I plugged my scanner in today while driving. Not sure what the values should be but it looked good. Lol. At idle was about 8 under throttle it would go up.

 

At idle it was 8 g/s??? Its should be close to engine displacement at idle. If its 8 g/s the maf has issues.

At idle what's your fuel trims look like? Short and long term?

 

I had to buy a new scan tool, mine was acting funny.
so at idle the air flow is 3.5g/s when at idle & operating temp.

 

Those number look ok. One question do you have an after market filter in place? I notice this with mine having an AEM dryflow. It will add fuel on idle bank 2 to to 5% long term. With stock filter all my short trims will be 0 longs will be -2 to -3 both banks at idle once warmed up.

 

Stock air filter. It has about 30k on it. Time to replace it.