Chevy Tahoe P0171 and P0174 Diagnosis | Drivetrain Resource (700r4transmissionhq.com)
P0102 OBD-II Trouble Code: Mass Airflow (MAF) Circuit Low Voltage Input (yourmechanic.com)
The lean codes are consistent w/a vacuum system problem. The engine just won’t run well, if at all, when the air flow sensor isn’t working. Could be an alternate explanation for the lean codes. A “low” circuit code could mean its precision power supply voltage isn’t reaching the sensor. Typically the precision voltage for sensors is 5 volts. I’d guess your best bet is to figure out the airflow sensor problem first.
Try cleaning the MAF sensor with a van of MAF sensor cleaner. Inspect the wiring to the MAF sensor and the connector at the MAF. Make sure the air duct between the air box and the throttle body is on secure and doesn’t have any gaps or tears.
Oops. Use a can of MAF cleaner. You probably won’t need an entire van of it. 
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Sounds like an air leak to me. A leak will cause all of those symptoms.
A leak either above or below the throttle plate (meaning the direction of the intake tract) will affect the MAF sensor.
OK I cleaned mass air it looked like a honeycomb not dirty at all and the open ends are on good but the thing that’s right on top of the throttle I think its a sender its real loose and my oil fill tube is also real loose
I’m trying to think what “the thing that’s right on top of the throttle” is. I’ve got a truck with a similar engine. Can you post a picture of the “thing”. Or describe it a little further?
its probably the TPS
Ya thats what it is its really its wiggle and I put seal stuff on the oil fill tube cuz that was real loose
If the throttle position sensor is loose, that’s probably why the truck is stalling. It either needs replaced or reattached, depending on where/how it’s loose. My truck is newer and doesn’t have one. They just bolt in with a couple of screws, in past experience with them on other engines.
Hi again well I put in new fuel filter new purge valve and new mass intake because a new code came up for low vacume for the mass air flow the code hasn’t came up again but the p0174 and 0171 still there and didnt see any difference after the new parts and I’m not sure but the smell of egsost that’s probably spelled wrong but that or burning coolant smell seems to be getting stronger I’m sorry to bother you but the shop just kept my car half a day and told me theres no way to know why its dieing till the mass air and purge valve get fixed and wanted 450 and a hole day to do it so I went and got the parts and did it myself in like 15 minutes and 134$ that’s why i dont go to auto repair shops they see I’m a girl and just tell me a bunch of bull thinking I have no clue what there saying anyways it’s just frustrating sorry to vent
No problem on the venting. So now it just has those two misfire codes and I’m assuming it runs poorly, idles kind of low, etc?
The difference between you doing it yourself and paying a shop is because they have something to cover called overhead and it is not cheap.
It is not because you are “a girl”. It’s economics pure and simple. You can mow your own yard or pay someone to do it and the same principle applies.
You can even do your own appendectomy and save a ton on medical expenses…and that HAS been done by a few individuals.
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