PO101 and PO171 engine codes

[tackett07]

Hey guys, Im new here, so I hope this is the right place to post this question.

I've been noticing my truck hasn't been running right. My check engine light came on so I took it to Advance Auto parts to let them read it.
2 codes came up

PO101 and PO171
I got on here and notice it was something to do with the Mass Air Flow. Can anybody suggest a reason to fix this.
Thanks guys

my truck is a 2007 WT Silverado.

oh and would this fit under the powertrain waranty?

[MT-2500]

Originally Posted by tackett07

Hey guys, Im new here, so I hope this is the right place to post this question.

I've been noticing my truck hasn't been running right. My check engine light came on so I took it to Advance Auto parts to let them read it.
2 codes came up

PO101 and PO171
I got on here and notice it was something to do with the Mass Air Flow. Can anybody suggest a reason to fix this.
Thanks guys

my truck is a 2007 WT Silverado.

oh and would this fit under the powertrain waranty?

What engine?
What mileage?

Power train is transmission and engine and rear ends and or transfer case..
Check with your GM dealer on other stuff that is under warranty.
Some stuff is covered under the federal emission warranty.
Let us know what you find there.

As for fixing codes scanner reading should be checked out and codes should be cleared and see what comes back.
Any add on air take stuff?

If code does come back you need to go threw the repair flow chart for that coder.
Is it all hooked up good?

[MT-2500]

Or you just asking for a reason to fix it or how to fix it?

[tackett07]

Originally Posted by MT-2500

What engine?
What mileage?

Power train is transmission and engine and rear ends and or transfer case..
Check with your GM dealer on other stuff that is under warranty.
Some stuff is covered under the federal emission warranty.
Let us know what you find there.

As for fixing codes scanner reading should be checked out and codes should be cleared and see what comes back.
Any add on air take stuff?

If code does come back you need to go threw the repair flow chart for that coder.
Is it all hooked up good?

Sorry,
its an V8 4.8 Vortec with about 33,000 miles
Its complete stock, I erased the codes just a few minutues ago, so we'll see what will come back

Thanks again!!

[tackett07]

Originally Posted by MT-2500

Or you just asking for a reason to fix it or how to fix it?

..asking how to fix it.

Is it a mass air flow sensor needing replaced. or could it be anything?

Here are what the codes read:
PO101- MAF or VAF A CKT Range/perf

PO171- System to lean (Bank 1)

and when I hooked the scanner up the second time it said the code number and then PD

I looked what PD stood for and it said Pending Codes are also reffered to as "continous monitor codes" and "muturing codes". Pending codes occur when the code has not occured a specific number of times, causing the code to mature.

[MT-2500]

Originally Posted by tackett07

..asking how to fix it.

Is it a mass air flow sensor needing replaced. or could it be anything?

Here are what the codes read:
PO101- MAF or VAF A CKT Range/perf

PO171- System to lean (Bank 1)

and when I hooked the scanner up the second time it said the code number and then PD

I looked what PD stood for and it said Pending Codes are also reffered to as "continous monitor codes" and "muturing codes". Pending codes occur when the code has not occured a specific number of times, causing the code to mature.

With a hard code the check engine light should be on.
Pending code is a code getting ready to set because of the problem there.
History or past codes are code that have set and cleared up.

As said clear code and drive and watch for what comes back .
if any do post back codes no.

And call dealer and check on your warranty on it.
Let us know what the dealer says.

[tackett07]

Another note. Today when I was leaving for work I notice the truck wasn't idling right, it kept trying to die. So put it in drive and it act like it wasn't getting any gas. It wouldn't go with my foot all the way down on the pedal. Now it seems like it's a fuel pump. But how can that be with the code said MAF. Any ideas what could be wrong

[MT-2500]

Originally Posted by tackett07

Another note. Today when I was leaving for work I notice the truck wasn't idling right, it kept trying to die. So put it in drive and it act like it wasn't getting any gas. It wouldn't go with my foot all the way down on the pedal. Now it seems like it's a fuel pump. But how can that be with the code said MAF. Any ideas what could be wrong

Seems like does not get it.
Only proper testing will lead you to the problem.

Are you going to the dealer or going to fix it yourself?

If you are going to DIY it.

Post back what code comes back after code clear.
Post back that code no.

If it is same MAF sensor code get the repair flow chart for that code and have at it.

[MT-2500]

A quick test on the MAF sensor is to unplug it and see if it runs different or better.
If so post back.
But that will set a code.
So you will have to clear codes again and run to see if any codes comes back.
Also make sure connector is plugged in good and no wire damage and make sure all air intake ducks are tight and no leaks.

[tackett07]

Originally Posted by MT-2500

A quick test on the MAF sensor is to unplug it and see if it runs different or better.
If so post back.
But that will set a code.
So you will have to clear codes again and run to see if any codes comes back.
Also make sure connector is plugged in good and no wire damage and make sure all air intake ducks are tight and no leaks.

Alright, thanks alot guys. During lunch I'll go back and unplug the sensor to see how it acts

[tackett07]

Originally Posted by MT-2500

Seems like does not get it.
Only proper testing will lead you to the problem.

Are you going to the dealer or going to fix it yourself?

If you are going to DIY it.

Post back what code comes back after code clear.
Post back that code no.

If it is same MAF sensor code get the repair flow chart for that code and have at it.

Where could I get the flow chart at

[MT-2500]

Are you going to DIY it?
Repair flow charts can be found in the factory repair manuals or All Data and Mitchell online DIY repair info subscriptions.

[tackett07]

Originally Posted by MT-2500

Are you going to DIY it?
Repair flow charts can be found in the factory repair manuals or All Data and Mitchell online DIY repair info subscriptions.

1st thing I'm gonna do is unplug the sensor and see how it drives. But I say I'll end up taking it to the dealer. I just hope it's the mass air flow sensor and nothing huge.

But after I unplug it and drive it. I'll let you all know how it does

It actually done this bout a week ago, kept acting like it was gonna die. But then it just stop so I let it go, but now it's back. So I better take care of it this time lol

[tackett07]

Alright, so I upluged the mass air flow sensor and then plug it back up and it seem to do better. Wasn't trying to die no more. But I notice when I did this it would make the truck shift harder. It would only do it when switching from 1st to 2nd, about 10-15mph.

Once I plugged the scanner back up it read 5 codes this time

Po101
Po102
Po113
Po172
Po175

I know that since I unplugged the sensor it added the codes. Should I erase these codes again.
Seems to me like it is the sensor going bad

[MT-2500]

Originally Posted by tackett07

Alright, so I upluged the mass air flow sensor and then plug it back up and it seem to do better. Wasn't trying to die no more. But I notice when I did this it would make the truck shift harder. It would only do it when switching from 1st to 2nd, about 10-15mph.

Once I plugged the scanner back up it read 5 codes this time

Po101
Po102
Po113
Po172
Po175

I know that since I unplugged the sensor it added the codes. Should I erase these codes again.
Seems to me like it is the sensor going bad

Yes clear codes and drive it.
And let the dealer take care of it if that is the way your going go.
There is No pay check for you or us figuring out the problem for the dealer.
That is what they are paid for and what you pay warranty for.
Let us know how it goes.

If it runs better with MAF sensor unplugged it points to a bad MAF sensor