P0174 and P0171 SES

[Dave_B]

So, just today as I was warming up the car this morning to head out to breakfast I go to jump in and notice the SES is on.

Pre-cursor

Yesterday I drove it in the snow on the way back from the range. So weather was cold and grill area did have snow all in it. No issues on the drive or anything like that.

Most recent work (little over a week ago) was the cooling system, all of it. During that I replaced the upper intake boot, closest to the air box.

So, it's Bank 1 and Bank 2 lean. No idling issues, and no loss of power that I've noticed.

I've read this could be MAF, DISA, dirty MAF, crack in Intake Boot, Vacuum leak.

Before I go throwing parts at it, I'd like to really track it down. So what are you guys' thoughts on proceeding? Clean MAF and inspect boot? Spray carb cleaner and search for vacuum leak? Common places for these types of Vacuum leaks?

Thanks guys!

[alexandre]

Definitely do a MAF cleanup before anything else.

Are you on stock airbox ? If not, oiled filters often foul the sensor and make it report false readings.

[Dave_B]

Should have mentioned that. Stock box for now.

Luckily I'm on my 2 week field rotation and won't need the car for 2 weeks and plan to look at this stuff after hours.

[BCS_ZHP]

Check that little "F" plastic connector on the upper boot. It's very easy to crack and not notice, and only a $5 part. The small diameter hose that attaches to the smaller fitting on that "F" connector is also suspect, it crystallizes from the underhood heat.

[aurelius]

Roll me the tumbling dice on the lower intake boot.

[Dave_B]

Picked up some MAF cleaner tonight. Out to the garage I go...

[Dave_B]

Well... MAF is cleaned now with CRC MAF cleaner, plastic F connector looks good, hoses on it also look ok. I inspected the lower boot as best I could with the upper still in place. Is there a specific place it cracks?

GT1 is coming this weekend, hopefully that'll get to the bottom of this, along with my SRS light being on.

[mLuMaN83]

I had same codes... Bad Disa. Just replaced it.
hope u get it all figured out.

[Dave_B]

What determines a bad DISA? Are there any tell tale signs?

[aurelius]

Well... MAF is cleaned now with CRC MAF cleaner, plastic F connector looks good, hoses on it also look ok. I inspected the lower boot as best I could with the upper still in place. Is there a specific place it cracks?

I recently saw a great photo that would answer your question but I can't remember where it is. But the answer is the little tube coming off the larger one. It is best to remove it so you can bend it and really see any cracks. It is extremely common to have a crack there.