Ok so i have a 2000 1.8t with a apr stage 3 kit and a gt2871. No cats either. I was noticing that i am down on alot of power it seems and sometimes my car does what seems like a misfire at high boost but i dont get any misfire codes or flashing cel. I am pulling 4 codes as following:

p0102-Mass or Volume Air Flow Circ Low Input
p0171-Fuel Trim,Bank1 System too Lean
p0113-Intake Air Temp.Circ High Input
p0118-Engine Coolant Temp.Circ High Input

I have tried clearing and they always come back. It said in vagcom that they were all intermittent. Coolant temp sensor is a week old and all sensors are cleaned. Also the oxygen sensors are both new i installed the universal bosch replacements and all wiring is good and tight. New spark plugs. Coil packs are not old. Idk if the maf is bad or not but on my vagcom logs it reads all the way up to 240 g/s at wide open throttle so idk if that is an indication of it being bad or good. It seems to read the airflow and at idle it reads 3.1 give or take. Please help me out.

 

Check for vacuum leaks.
You might need to replace the MAF.

 

there are absolutely no vacum leaks and engine compression is also good.

 

+1 and your Coolant temp sensor.

 

i said i just replaced my cts and it did this before i replaced it too.

 

try using maf cleaner before spending 100+ $ on a new maf

 

tried maf cleaner along with cleaning every other sensor. but the maf reads fine on vag com and idk what else to look for

 

update!!! when i take out the 3 bar fpr that is for my unitronic software and put in my old 4 bar fpr all the codes go away but ocasionally i still get some studder like misfiring but no cel or codes.