VE Problem

[fwdGTP]

Well, i had been working on my friend's Cobalt, and he wanted me to reload the stock stage 2 tune back onto the car for dealer purposes, so i did so. Now his car seems to run very slow at times, and have some random issues. Also, i was comparing a scan from last night to an old one when he was originally running stg 2 w/ 2.9 etc (same mods), and it seems that the map is about 2 psi higher, which may just be from it being really cold outside, and the VE is very low, less the 1 lb/min while cruising, and about 4 lb/min at 7k, when it used to show 4 while cruising and 25 at 7k. I have not had a chance to try reloading the tune yet, because my laptop battery sucks, but if anypone has any ideas why it's running like this please let me know. Also during the second little wot run through 2nd on the broken hpl is seemed to cut out half way through, so if anyone has an explanation for that it'd be cool lol. But yea, the 150mph one is old and the broken one is the one I recorded last night, these are both on the 100% Stock GM Stage 2 tune. Thanks.

[dont_blink]

I too have seen this before. It is because the car is fueling off the MAS. Unplug it and tune your VE table and you will see it reading VE airflow properly. It's there as a fall back of sorts for when your MAS goes bad and to check to make sure the MAS is functioning properly. If you don't tune this when tuning your MAS, you end up with a big discrepancy in fueling, which could make the car feel like dog poop.

[Pyros777]

I'm sure dont blink just forgot, but dont unplug the MAS, it also serves as your IAT sensor. Just fail it in HPT.

[dont_blink]

It serves as a primary IAT sensor, not the one that actually adjusts timing though. You can fail it at 0 Hz, but the PCM will still read it. What I meant by that was unplug it and it will show you how far off your VE table is and why the car is running like dog poop.

[fwdGTP]

The thing i am confused about is why the exact same car with the exact same tune car be coming up with such different numbers, especially ones that are no where near realistic, probably the iat you think that set them off?