I let my car idle and at ~980 rpm, the MAP was reading ~.7 bars. This translates to 20.7 in-Hg (70 kPa). This is way too high. Does this mean I have a vacuum leak? I know my brakes haven't been working at all. They are extremely hard to push down. But, my MAF reading ~ 13 gm/sec @ 980 rpm. I guess this could also be a reason my car won't idle down. It idled fine before my M6 swap. Any help is appreciated.

Benji

 

How radical is the "Joe O cam"? That's the most likely source of low intake manifold vacuum. Valve adjustment and timing gear alignment could also be problems. A good tune can sometimes improve the vacuum on a high overlap cam.

What changes did you make to the program for the A4->M6 swap?

 

I didn't make any changes, except turning off the codes that were being thrown because of the computer not being able to find the A4 (ie. TCC Enable Fault, 3-2 Downshift Feedback Fault, etc.). The cam really isn't that radical. It is similar to a GM847, but with smaller lift numbers. The brakes worked when I first put the motor in the car (on the old Hotcam tune), but after it was dyno tuned, they didn't work anymore. I didn't think a tune could cause that. I guess I could get a vacuum guage to verify, but the MAP sensor should be reading correctly. I appreciate everything.