New Scanmaster, bad maf? Iac?

[BigTurbo6]

Just hooked up the scanmaster and was trying to set the tps and iac. Tps was simple, but the iac would just slowly drop to 00 no matter what we set it to. So then we drove it and checked the MAF. 06-130 was the range. Could a bad maf cause the iac to change? Also if i pop it into gear the iac numbers climb slowly to 175. 02mvs were 850 in 1st, 750ish in 2nd , 730ish in 3rd.
Any help would be appreciated. (also where should i get a maft+ from?)

 

[scottyb]

At idle, MAF of 6 is normal.

If you have difficulty keeping the IAC above 0, then I might suspect a vac leak, post-TB. Turn the set screw out a bit so the throttle blade closes some. Check/reset your TPS to .38 - .44 and watch the iac numbers again. The cruising IAC numbers aren't really significant unless the engine has difficulty recovering from throttle closing, deceleration and re-establishing idle.

If those O2 numbers are WOT, you're REALLY pushing the lean side. Are you getting knock? Cruising, the O2's should bounce all over.

 

[BigTurbo6]

Well i drove it work and back today. 02s bounce all over, iac seemed to finally start to sit at 48. Its a start i guess. Still the maf seems screwy, it reads 05-06 at idle and around 20 while at a cruise, but max out at 180 during WOT. 02's are more difficult to read cuz they move a bit, but 830->850 at WOT in first, 770ish i guess in 2nd, 3rd....hard to tell exactly....what should this stuff be? I've got fuel pressure at 45lbs line off and it raises with boost. Boost is at 14lbs. 30lb injectors, Thrasher 92.

0.0 knock throughout btw

 

[scottyb]

Generally speaking, those numbers aren't out of whack.

Your MAF idle number is good, but 180 at WOT seems rather weak. In turn, this may explain the low O2's at WOT. Make sure there are no leaks between the MAF and the throttle body. If you have the original flex hose, inspect it thoroughly

You know how to do recall on the scanmaster, right? Bump the boost up a pound at a time until you get a little knock, them back off a hair. I would expect the MAF to be approaching 255 at 16+psi....I think????

 

[scottyb]

ON SECOND THOUGHT, maybe bumping up the boost with O2's that low is risky bizness.

I think your first approach might me to lazy MAF, or an air leak after the MAF.

anyone else????

 

[BigTurbo6]

I have one of those chrome MAF pipes to the turbo. All clamped on pretty well. I think i'm gonna see if i can bang on the downpipe and get some knock to make sure the sensor is working before i push it. If it does then I'd like to turn the boost up a touch, but I've got the wastegate rod as tight as it'll go and my solenoid doesnt seem to be working...have a boost controller thing i bought but it seems like junk because it either doesnt do anything or boost is wide open.