P101, P172 & 175

[Sdp1234]

I e had this truck for about 5 months but I just drive around town so far. I’d like to pull a small trailer but I noticed it is sometimes sluggish from take off. Started to take off faster lately to test things out. At one point last week I got a check engine. Engine would dog out then sometimes surge to the power I’d expect from a 6.2.

Codes are 101, 172 and 175 Over all it has seemed to run pretty well.
Ideas?

 

[Big Mama]

All of those point to the MAF sensor.

 

[Sdp1234]

Hmm Replaced it last month...

 

[Sdp1234]

Any ideas what should be my next step?

 

[Big Mama]

Anywhere air is getting in past the MAF sensor. I had this once and my intake tube after the sensor was loose check for cracks too.

 

[Sdp1234]

I’ll check in th emorning Thanks

 

[Sdp1234]

I don’t see any cracks or problems with the tube sealing

 

[Sdp1234]

Cleaned and reinstalled the original MAF that I replaced a couple weeks ago because of a p0101. So far no codes and it doesn’t hesitate anymore???

 

[Big Mama]

Wonder if the original MAF was just a loose connection. If you can take the other one back do so. You know it’s no good. No hesitation makes sense. Right amount of air and gas. Glad it’s fixed.

 

[Sdp1234]

Now it’s time to tow something for the first time. I will not tow much but I wa t to be able to pull a 5k camper when necessary.

 

[Big Mama]

In all of this I didn’t see your year but if it’s a 6.2 it’s at least an 07 Denali like mine. The weak point on these is the chassis. My boat weighs about that much and I tow it and other trailers fine. Look on the driver door jam for limits.

 

[BG1988]

Cleaned and reinstalled the original MAF that I replaced a couple weeks ago because of a p0101. So far no codes and it doesn’t hesitate anymore???

connections have a way of making them selfs loose some going as far as clipping them selfs

 

[Sdp1234]

Figured it was “too easy” or “too good to be true”


Now my intermittent p0101 is back.

History
Throwing intermittent p0101 code. Typically when I push it a bit goes away if I babied it

Replaced the MAF
Code seemed to go away but there was a hesitation and/or sluggishness when taking off. Every now and then I’d get what seemed like full power but not typically.

Started throwing p0101, p0172 and p0174.

Cleaned and reinstalled the original MAF. Power came back and hesitation went away. No codes for a 4 days. Today the p0101 came back intermittently


Not sure about these MAF’s Or is it something else

 

[Big Mama]

Let’s bring in some help but my bet is a bad MAF or air after it. How about it boys?
@iamdub @swathdiver @HiHoeSilver @kbuskill @NathanJax

 

[Fless]

Anywhere air is getting in past the MAF sensor. I had this once and my intake tube after the sensor was loose check for cracks too.

Maybe a closer inspection of the intake tube would show movement or an air gap under heavier acceleration (as the engine twists on the mount).

 

[iamdub]

Did you clear the codes when you installed the new MAF? The PCM might be doing better with the old MAF because it has already compensated for it's input. The new MAF totally skews these tables so it runs worse.

The MAP sensor also plays a role in drivability and load calculations so there could be something going on there.

I'd reset the PCM and try the new MAF. The way I've always done it is to pull all ECM fuses with the engine running, waiting about 10 minutes, reinstalling the fuses then starting as normal. It may stall a few times as it relearns idle. Don't try to help it by giving it throttle. Let it do it's thing and just restart it.

 

[swathdiver]

P0101 means the metered air is not matching the throttle body or MAP sensor. Check and triple check all around for air leaks of unmetered air and make sure your Mass Airflow Sensor is GM OE or ACDelco Professional.

 

[HiHoeSilver]

I like dubs idea about the pcm.

I am assuming your title is correct and you have/had two rich codes, not what you typed this morning with one rich and one lean. Correct me if this is wrong.

When is the last time you put a new air filter in it?

 

[Sdp1234]

P0101 means the metered air is not matching the throttle body or MAP sensor. Check and triple check all around for air leaks of unmetered air and make sure your Mass Airflow Sensor is GM OE or ACDelco Professional.

I’ll get someone else to help me double check the input tube.
The replacement MAF was from parts geek. I guess maybe cheap could cause me the problem?

 

[Big Mama]

For sure but what I forgot to mention is what Dub said about resetting the ecm. If I’m not mistaken the old codes just went away when you put the old MAF back on. For sure cheap can cause problems especially on a fairly inexpensive part to start with.