Strange Jerking While Coasting

[ENVYOSXR]

Hi guys,

I have this wierd shudder/jerking happening when coasting at low speeds. Only noticed it at anything below 60kmh when just rolling, it sometimes starts to jerk like something gets out of rythm. If I push the clutch in and release it, it comes good again. Same deal if I put the foot on the gas it comes good.

Some info on the car:

- 310rwkw

- 6sp Manual (Transmax Z Fluid)

- 05 BA MkII

It used to only do it rarely in third, but now it happens more fequently. I am think diff bushes maybe? Any ideas would be great!

[exarsixturbo]

Hmmm.... no one likes jerking while at low speeds or strange jerking while coasting..... you will definitely start to jerk when you get out of rhythm.... and its ok if it happens more frequently in third....

I suggest putting some Barry White on the CD player, turning down the interior light a bit, maybe having a bottle of wine, and you will learn to enjoy it once you get in the rhythm!

[RIXT]

BARRY WHITE

Mate sounds bit like your centre diff bush see P@ he will sort you out for super pro gear pretty cheap !

Ric.

[dashturbo]

but really..

is the power fluctuating? or is it when the throttle comes on and off your getting jerking?

My FG has always been jerky since I got it. even when the cruise comes on or off on the freeway.

and when the engine is cold (open loop) the power feels jerky.. but I can live with both..

oh and what do you mean by jerk? a thump through the drivetrain?

[ENVYOSXR]

haha how did I know I was going to get a response like that.

its hard to explain, basically its sounds like diff clunk one after another but only happens when the car is rolling not under acceleration or brake. if I hit the gas it stops and if I push in the clutch.

when I take the foot off the gas and go down a slight incline it will be fine some of the time, but other times it wont.

I have a feeling it is the centre diff bush also, if I replace this what else should I be replacing while I am at it in that ares?

I am also due for a new clutch could that be part of the problem?

Thanks guys

Edited 10/12/09 11:31 PM by ENVYOSXR

[IH8TOADS]

but really..

is the power fluctuating? or is it when the throttle comes on and off your getting jerking?

My FG has always been jerky since I got it. even when the cruise comes on or off on the freeway.

and when the engine is cold (open loop) the power feels jerky.. but I can live with both..

oh and what do you mean by jerk? a thump through the drivetrain?

Won't be your clutch.

Open loop lasts for a minute or so, so I doubt you will be in open loop by the time you start driving.

The 6sp ba is born jerky, even with a fresh diff bush. You can modify the accelerator pump logic and dashpot

settings in the tune if it $hit$ you that much.

[ENVYOSXR]

fair enough, thanks for the advice guys

[dashturbo]

I wouldn't be too quick to dismiss the clutch. I haven't seen a falcon one since EA, but all the clutches I've seen have take up springs, that supposedly smooth the application. Basically four normal springs (look like valve springs) between the clutch material and the input shaft...

Sometimes, they get damaged, crack, break, fall out. Or in general are too soft and can cause the kinda thing your talking about. It may get better with a new clutch..

[XR06T]

centre bush just behind the gearbox or the centre diff bush. both are easy to check and you will notice straight away if either are worn.

here is a pic of mine after I finally changed it, I had a similar clunking to what you describe:

Edited 15/12/09 06:35 AM by XR06T

[dashturbo]

that's Mashed!!