My compression test came out 90s on the front rotor and 80's on the rear. What should I expect to see there? Compression is obviously a bit low, I heard it should be anywhere from 80-140. The dood at the shop said he found a vacuum line that was broke, and a switch that was broke also... any clue what these could be? Anyone have any ideas... let me know.. (car is having idle problems, stalls sometimes when A/C is on) and it's not a MAP sensor problem. Any idea on the compression results either?

 

You need to know what EACH of the three readings on each rotor face is, three in the front, three in the back for a total of six.

 

does the car idle ?

if it does and has power the engine is fine

 

Those were just peak readings... =/

 

if those were peak readings, then your fine...IF the peak readings are the same for all 3 sides of the rotor.

 

Yes the car does idle... but rough. Can vacuum switches cause all this crap? Apparantly one of them was busted....

 

Peak readings are the highest number out of one of the three pulses, it tells you nothing.
He needs to take it to someone who has a rotary compression tester and do a real test.

 

The busted vacuum lines can cause your car to idle funny, address that problem as it's an easy fix then get a real compression test done.