My car has roughly 13,500 miles on it. Since the day I purchased it, it has had this very annoying problem. I tried to convince my self it is normal (so has two dealers!). I really don't think that it is normal, but I have no idea what it could be for sure. I've searched through all of the threads concerning the SC IC pump and clutch, but never found a definitive answer.

When accelerating from a stop leisurely, at about 2300 rpm (when the sc kicks in), the car surges aggressively. But, it's not really a surge, more like a major draw on the engine. It is definitely not smooth like the car should be. The SC kicking in should be transparent, but it is far from that. It's not the trans. Passengers always ask what the deal is and if there is something wrong. I just tell them that it is the SC kicking in.

When accelerating abrubtly, the problem is less noticeable, almost non-existent.

This is a very annoying problem and really makes the car less enjoyable because I'm dreading the possiblility of it being something I can't correct my self. I hate taking it to the incompetent dealerships.

Any information or guidance is much appreciated!

 

CG, can you post a video of it?

 

I'll try to explain this as best as I can. When you leasurely accelerate the supercharger isn't on. The ECU doesn't see the need as you are just putting along. Well you see the supercharger must turn on before 3,000 RPM because that is the way it is designed (belt load would be too high if engaged later). So once you get close to that RPM mark that clutch has to mate up or catch up with a rotating assembly that is spinning really damn fast. I don't know of anything that could make it a smoother transition.

Now like you were saying when you stab the throttle the engagement is almost non-existent. That's because a different scenario just happened. The ECU saw that you needed to get going in a hurry so it engaged the supercharger much sooner thus eliminating the need to "catch up" with the rest of the rotating assembly.

Bottom line? I try to stay away from that occurrence buy leaving it in D. Then when I put it in manual mode I change my driving technique to be more sudden. Understanding just how this car works and what to stay away from (such as this engagement) should keep you happy for many many more miles to come.

 

This is the first car I've owned with forced induction, especially one that has an electromagnetic clutch assembly. I figured some of the engagement would be noticeable due to the mechanics surrounding rotational mass and clutch engagement; however, mine seems a bit more abrupt. I have the slight chirp too. I found the following on the MB forum. Msheredy, seems like you were trolling this site too. Thanks for the info. I'm going to drive it for a while until I get a chance to bring it to the dealer along with lots of print outs from the MB forum.

http://mbworld.org/forums/showthread...ight=clutch+sc

 

I believe that is 'normal' as well.

All 5 of the SRT's I have driven have done this - I always assumed it was the S/C engaging.

The 'chirp' I have not had...other than the tires

SQ