Repost (I can't seem to get any responses in general forum)

I just got my 08 G35 6MT on Friday. Drove it for about 500 miles going from Houston to New Orleans. Everytime that I let go the gas pedal while still in gear the G gives me a tug/pull (kind of a little bump) about 1-2 second after I let go the gas pedal. This happens even when I tap the gas very lightly just for a second. When I let go the gas while in gear, the G gives me a bump 1-2 seconds later. Is this common with 08 manual transmission G's? I've been driving manuals almost all my life (86 Honda Accord, 94 Honda Passport, 2000 Audi TT, 2005 Audi A4), and I don't recall ever having experienced this bump sensation when I let off the gas pedal while still in gear. Any comments regarding this matter is deeply appreciated.

 

I think I might know what you're talking about. I have an 08 automatic and it does give a sound like you described. This might be common.

 

This is normal for the most part. I have an 08 S 6mt and have the same thing. It happens less when your in a higher gear but it is definatly annoying.

 

Yup. I've had this also and asked about it here. Some say it's driveline slack. It is annoying though as it definitely detracts from the smoothness. As you've mentioned, you could be in 4th gear and very gently depress and let go of the throttle and get a "kick" a second or two after.

This is my first rear drive car--can anyone who has had a RWD car confirm that this is normal?

 

That's perfectly normal in a 6MT

Replace your drivetrain bushings with stiffer ones and the slack will lessen, reducing that bump. (the DBW partly contributes to this, but you can't do a whole lot about that at this point)

You shouldn't be feeling it much in 4/5/6th gears...

You should be REALLY feeling it in 1st and 2nd unless you're letting off the gas VERY gently, and should be fairly noticeable in 3rd.

This also happens in my other MT cars...

Also, it looks like your other MT cars are all FWD... FWD doesn't have a driveshaft that transfers power from the front to the rear (source of drivetrain slack)

 

Yeah this is completely normal in a manual car.

 

mine does it. and its normal

 

Driveline slack of RWD Manual + Drive-By Wire = Tug.

No throttle = Closed Throttle Body Plate = Decel mode. Decel mode = Tug.

 

Thanks for all the comments guy. I must admit that I did not understand some of the explanations with my feeble knowledge about cars. But I feel better (sort of) knowing that it's a common event, as opposed to a problem with my new G35.

I started noticing it more when I was cruising at highway speeds on 6th gear. I'd let off the gas because the traffic was slowing down, and then I'd feel that jerk. My girlfriend kept wondering why I was taping the brakes. I wasn't. I started testing the car by just barely touching the gas pedal and letting it go immediately. Every time I did that, I'd get that jerking effect about 1 second after I let go the gas pedal.

It does appear that the faster I am driving (on the same gear) when I left off the gas, the smaller the jerking effect. For example, when I was driving at 80+ mph on 6th gear, and I took my foot off the gas pedal, the jerking effect was barely noticeable. But when I was driving at 60-65 mph on 6th gear, the jerking effect was much more pronounced.

 

I had the same issues. Here is a link to a thread I started on the topic. Pretty much more of the same as far as explanations go. But like you, I was glad to hear I wasn't the only one having this issue.

 

Thanks for sending me the link to your thread. The jerking is annoying and my girlfriend was wondering why I was tapping the brakes. Someone said something about a "cold start TSB" on the other thread as something that reduced the jerking. What is that?

 

That TSB applies to the 07 models only I believe. However many did report that it fixed this problem. So maybe we will see one for the 08's eventually.

 

Thanks, but what does the TSB actually do? From the name "cold start TSB", it sounds like something that you use for cold weather related stuff.

 

I think that was the one for the engine surging before it reached operating temperature. It was basically a reflash of the ECU, which had the side effect of smoothing out the throttle response and (for some) getting rid of the pull when letting off the accelerator.

 

"Reflash of the ECU"?? What is that? Sorry, I am totally car illiterate. I can change the oil and filter in my car and top off the fluids. That's about it.