Hello all.
I am having a MAJOR PROBLEM!
i have a 2005 mcs with bolt ons, alta i/c, alta 15% pulley, alta 2% crank pulley, alta intake, msd coil, firebraid wires, ngk one step colder plugs, megan headers, test pipe, alta catback exhaust, Detroit tuned Bypass valve.
about a month ago i was on my daily trek to work and all of a sudden my serpentine belt snapped, had to pull over tow it home. when i got i jacked up the car and ordered the belt. nothing else looked out of the norm, so i replaced the belt. let the tension out of the tensioner and the tensioner didnt spring. so i went to mini and replaced the tensioner with a brand new tensioner, jacked the car down and proceeded driving everything was fine but the second i would give it throttle and make boost.the car would throw a check engine light and read the following codes. p1689, p0107, p1242,p1109, p0304.. the car would go into limp mode. pull over shut the car off waited 10 seconds would start it back up and everything was fine again. slow acceleration was fine but once again the second i would open the throttle again, it would go into limp mode. so took it home (creeping). read a little bit on here(actually alott) and my first choice to change and look at was the by pass valve. so i went ahead and changed it out with a detroit tuned bypass valve. then the problems really began.i i start the car up and immedietly when i start it up the rpm revs up on its own. then had the roughest idle and would drop to about 500 rpms, almost stall out and then catch itself and continue with a rough idle. so with further reading i saw and proceeded to replace the plugs. it was a little better at first but then the same problem same codes. so i continued. replaced the coil, the wires and the problem was still there. i went to the dealer today and replaced both map sensors. and yet still the problem persists. can anyone please help me out! any input is greatly appreciated the idle is terribly rough, and the car is reading 4-6lbs of boost at idle. . if you try to rev it up it almost doesnt rev up at all. its like your not even hitting the throttle and the rpms go no where then other revs the rpms go up in sync with your foot. the supercharger is very whinny and loud (constant boost).

thank you guys so much any help wouyld be greatly appreciated

 

Sounds like you may need a crank pulley, replace it with an ATI super damper and don't worry about it failing again. You need to pry on the crank pulley and see if the rubber on it is coming apart.

 

hey Way thanks for the tip. that was another item to check off down the line unfortunately i already have the alta lightweight crank pully.. so no rubber to peel apart :/ .. another thing i wanted to add to the original post was my car is smelling very very fuel like. while running it just smells like pure gasoline. ?!?!?!

 

Any update on your car? Im experiencing some similar problems. My thread.