dawheat

I've been noticing this occuring a bit more commonly, especially when the car is col and in lower gears.

While accellerating, around 4-5K, the rear seems to shudder a bit and then dissapear higher up in the rpm range.

Diff and tranny fluid was changed at 23K miles. Any thoughts if this is normal or whether it would be something (diff?).

I am the second owner, but since 18K, no burnouts, but there has been a open lapping day on it. Stock power, 04. Thx.

mikegarrison

My car is doing the exact same thing (mild shuddering from the rear, mostly when the RPMs are between 4-5K in lower gears, more often when car is cold). I suspect it is early symptoms of the CV joint problem. I will try swapping the inboard CV joints (perhaps this weekend) to see if the symptoms go away.

My car has 46K miles on it. Not lowered.

xviper

CV is a good guess. Also take a look at the MAP sensor TSB (Technical Service Bulletin) from your dealer.

mikegarrison

Whatever it is with my car, I'm fairly sure it's not the MAP.

xviper

Hehe, meant that one for dawheat. Most "car guys" will be able to tell the difference between an engine hesitation and one caused by the rest of the driveline.

hotmayo

I dunno, I've noticed that since getting the car brand new. For me it's not even a "shudder" shudder, but more like a vibration. Not even a vibration, it's so slight. It almost feels like the tire tread, it's a very high level vibration. Is that the kind of feeling?

dawheat

Thx guys, next time I'm into the dealership, I'll ask them to check those joints.

ol' dood

Sometimes, if the rear crank seal starts to leak, you will get a little bit of oil leakage onto the flywheel surface which can make the pressure-plate skudder as it engages the friction plate to the flywheel surface. This can cause that harsh clutch engagement. Try this, put a fresh sheet of newspaper under the car when you park it overnight. Before starting it, pull the newspaper and look for an oil spot indicating leakage. Pay close attention to where that spot is relative to the engine/transmission juncture. The aim here is to pinpoint where the leak is. Now, if the rear main seal IS leaking, don't think it can't get onto the flywheel surface. Oil is an insidious agent and will migrate easily. It would only take ONE drop of oil on the flywheel surface to cause the skuddering. We have a dry clutch setup.

mikegarrison

Well, I swapped CV housings this weekend. A very short test drive indicated marginal improvement (or maybe not any at all). There was no visible sign that the CV joints had started to go, and the grease looked quite good. So if I was having a CV joint problem, it must have been at the VERY early stages.

I have the RA1s on right now for a track day. A quick test drive on those and I didn't really notice any issues. I'm now wondering if it might have been a subtle wheel balance problem.

xviper

Mike, in your case, I think this is a pretty good guess. A CV joint issue should be most prevalent if you accelerate in a moderate to hard fashion. An odd vibration at a constant road speed is more indicative of wheel balance and would change as speed changes up or down since an unbalanced wheel would have a tendency towards an ideal harmonic rotational speed. It'll get steadily worse as speed goes up and as you continue to speed up, it tends to lessen.