Anyone experiencing shuddering on initial acceleration under 40mph. Does it everyday, all day, I have an appointment for this coming Monday morning. I have 12k on the dial, hope this is a simple fix. Anyone else with second gen having this issue? Saw a thread on the first generation with this issue, just wondering if any second gens are having the same issue.

 

Yes, I have that sometimes when traffic is slow and then picks up. Trans seems to be in the wrong gear and it's bucking like a M/T.

 

No bucking, just shuddering ever so slightly. I'll see what they say on Monday!

 

Can ya define shuddering?

 

Shudder/flutter it is hard to describe. Its weird but noticeable everyday I drive it. It's only on initial take off, light acceleration, usually under 40mph it shudders for 2 seconds and then its fine. Its been doing it for about 2 weeks, so I made an appointment for Monday.

 

Do you mean like a vibrating noise kinda shudder? I started experiencing this after I installed my intakes. I thought it was something loose with the boxes or tubes but nope.

 

Definitely not vibration, it is a shudder like driving over a ripples in the pavement for a few seconds. But its not in the tires, it is under the hood. I know it sounds weird.

 

YEs, there have been threads on this too. One theory is that it's the tranny switching from its locked / semi-locked configuration as you hit the gas - makes sense to me.

Regardless, it's only a quick shudder on mine (say, two "beats"), then it just moves forward.

 

Yepper.... I feel that too - cold engine - under 40 MPH, light acceleration, it's NOT a vibration but a "shuddering" - like going over small bumps, very momentarily, happens usually once on the intial acceleration, then it's Gone. Maybe it's a cold engine/tranny thing. I suspect that's it.....I applied the 028 TSB ECU upgrade about 4 months ago. I can't remember if this was experienced B 4 That upgrade or not??? The upograde did alleviate a Hard 3rd gear up shift with a cold engine and less Touchy Throttle.

 

028 did not fix cold start issue for me but 045 completely eliminated it.

https://g35driver.com/forums/showthr...ght=Cold+Start

 

i have begun to notice this since i passed 20k miles a few weeks ago. does it even at interstate speed. it happens after i am off of the throttle and try to roll back onto it. I had looked around in the factory service manual i have and the best thing i could find to fit it was that the torque converter is going from full lockup to unlocked or the the other way around.

on the FSM it shows various speed areas and the gear you are in when it will lockup. all of them fall under the speeds i feel this at.

 

Have you gotten your computer reflashed for the cruise control fix yet? If not, do so. It may fix your problems.

 

It is at the stealership now, I have no idea what they are going to do. I'll post what they do or tell me tomorrow.

 

I have experienced this "shudder" event myself. I notice mine when the rpm is below 1500 and between 40 - 60 km (not sure what that is in miles). When you accelerate a little harder it goes away. It only happens when I am trying a smooth slow acceleration from the low speed. As mentioned in a previous post, I think it has to do with the trany not responding to the right gear at the appropriate speed. Doesn't happen when I drive in DS mode.

Will be interested to hear what your dealer has to say......

 

Well I got my car back. They of course said they could not duplicate the shudder. So I asked for the shop foreman, I took him for a ride and we felt the shudder more than 10 times in a 3 minute ride. He said he had his tech drive him because he was in the back seat checking for my other complaint (window noise in the rear) which he also said they could not duplicate. He then went to look to see if there were any TSB's and he said there was one on the tranny. So he ordered me a valve body assembly and said it would be in within a week. Can someone explain to me what a valve body assembly is? Also, could someone tell me if there is a TSB for a wind noise in the rear passenger area? I also asked them to check out why when I pump 6 to 7 gallons of gas it won't take anymore gas? It gets so annying so I have stop, pay for the gas and finish pumping. He said they filled my car up and it didn't do anything abnormal. He said the car is only allowed to pump so much fuel per seconds, that sounded like crap. Is there a TSB on the fuel pumping deal? If so, please direct me to the TSB, I need to print these out. Thanks again everyone.