When my car is cold, and I am pulling out of my driveway (I say cold, but it is 110*+ in my garage), as I put it into 'D' to take off up my street, I get a 'hiccup' upon first pedal press. It is slight, maybe 1/10th second...but it acts as if there is a lack of spark, and over abundance of fuel, or not enough air. This is not a severe or harsh pedal mashing, but a leisurely stroll type take off. I am just normal driving when I get it.

I almost assume it is something that is relative to supercharged cars - but I could be wrong. It only happens when the car is first started.

For the record - this was before the sprint booster. Just remembered to ask about it and wanted to see if it is common amongst all SRT's or just mine. I also wondered if this had anything to do with my 'hard starts' and long cranking times. It is slightly resolved or ignored with the sprint booster installed, but I think it is just a band aid because the throttle response is much quicker. I can still feel a slight hesitation but it is greatly shortened.

Also, this doesn't seem to be as severe when it is in 1st gear as opposed to D...seems much worse in 'D'.

Either way - it isn't a big deal, just wondering if it is normal or if I should ask about it at the dealer. Could very well be some sort of open loop mode or something similar for the car when it is not at operating temp. Thought I'd ask!

Thanks,
Shawn

 

Common complaint. It's almost as if the car is just waking up. It's normal...

 

Well, with that said - it is pretty much non-existent with the Sprint Booster installed on it.

Thanks for the FYI NeverEnough.

SQ

 

Mine does it also.

 

This hiccup you are experiencing is the supercharger clutch engaging. It is common and nothing to worry about. Several SRTs, SLK32s & even the E55s experience this.

 

I figured it was related to the supercharger...

Thanks for the heads up.

SQ

 

Mine has the 'hiccup' too.

 

Mine has it also.

 

I still get the occasional hiccup when I first start off even with the sprint booster.

 

I don't and never have. So now I'm starting to worry...

 

I wouldn't worry about it. Not everyone experiences this on the Benzes either. Try this one though. Put your car into 1st gear at a stop light/sign. Take off normally and slowly build your RPMs, around 3,000 RPM you might feel the jerk. Try it out next time and let us know.

 

Mine does it too. I thought it was strange and was gonna ask when I had it in for it's first service. Now I don't have to. Sweet!

 

At 3,000 RPM, yes, I definitely feel the SC kicking in. But ShawnQ's first post in this thread explained that:
That sounds different to me: a cold car; just taking off slowly; first pedal press; a leisurely stroll normal drive cold start from the driveway. I do get the very slight kick when the SC engages @ about 3,000 RPM, but not in the conditions I understood ShawnQ was describing, since I usually don't hit 3,000 RPM for a few blocks when taking off from my neighborhood. Any other time, though, I'm happy to feel the hiccup since I know the fun is about to begin!

Thanks for the tip and for the reassurance. See - no more worries, and I feel better already!

 

Yes, mine experiences this as well.

 

 

I've noticed the same thing when first starting.

 

Knowing almost nothing about cars, I'll ask...

Would this problem go away if you simply revved the engine before putting it in gear?

 

I will answer that question tomorrow AM when I leave for work.

 

It may help that problem, but could cause future problems with the auto tranny. 'Neutral dropping' is a no-no!

SQ

 

Hmmm. I've got the cold start hiccup, but I don't notice ANY surge at 3,000 rpm when the supercharger is supposed to kick in. Now I wonder if something is wrong...?