Drive train shunt at high speed.

[stickshift]

I recently drove down to Plymouth (220 miles to see my brother) last week with my wife and two girls and luggage and all the usual women’s paraphernalia (one teenager and one eight year old that thinks she is a teenager). Therefore, the car is well loaded.

The problem I have is, when I accelerate from 60 to 70 in fifth gear there is a very noticeable shunt or “kick in the back” i.e. everyones heads resemble the whiplash effect and the opposite happens when I take my foot off the accelerator i.e. all heads in their laps. The problem is worse when cruise control is resumed after slowing down, I press resume and bang in the back, big jerk and off we go.

I suspect an engine mount if it is, which one would it be? Alternatively, could it be a software issue where the fly by wire throttle is getting the wrong signal?

[Gsi3.2]

if it is mounts then it would only be the fore and aft ones onto the subframe that would cause it.. the rear ones do get the most abuse..it's the speed that makes me wonder if it's something else, as if it was the engine mounts it would do it no matter what speed you took up the power in again..

time for you to have a play and see if it does it at any other speed range..

[VauxVeteran]

CC is a bit jerky anyway.

[stickshift]

The reason I suspected engine mounts is It's a 2.2 petrol 52 plate, its done 27,000 miles and the torque is starting to build @ about 3000 RPM so might not be as noticeable @ lower revs/speeds. also forgot to mention that when moving off from standstill or @ low speeds in 1st and 2nd gear only (around 5 MPH) there is an occasional noise from the front that sounds like a metal spade being scraped across some tarmac which only lasts a couple of seconds then disappears. Ive heard the noise on another "c" a while back it was a 1.8 which might also be engine mount related this only happens when the engine has warmed up though?

Are the mounts hydraulic or just rubber? The reason I ask is I thought that hydraulic mounts have variable rates at different levels of torque/vibration being put through them a bit like gas filled shock absorbers on the suspension and might act differently @ varied speeds.

If it's not the mounts could it be dreaded DMF?

CC is a bit jerky anyway.

I know it's not the smoothest but this is quite severe.

[Spikey©]

If it's not the mounts could it be dreaded DMF?

I think it's only the diesels that have the Dual Mass Flywheel dude.

[stickshift]

I think it's only the diesels that have the Dual Mass Flywheel dude.

Nope these do too.

[Karl]

sounds the same as mine did, engine and gearbox mounts had had it....

[VauxVeteran]

The scraping noise is most likely to be the handbrake shoes letting go, does it do it all the time or just after a long rest, i.e overnight.

[badge25]

My brother had the same problems on his old fiesta. we eventually found one of the engine mounts had come loose just enough to move when the power was applied. tightened it up and it was fine. we replaced it eventually as the thing kept comin loose every 400 miles. could be worth a look!

[stickshift]

The scraping noise is most likely to be the handbrake shoes letting go, does it do it all the time or just after a long rest, i.e overnight.

It never does it from rest/cold, only does it after a about five/ten miles when it has warmed up and it is definitely coming from the front. I noticed it more when I was driving through narrow hilly streets (Padtow, Cornwall). I had to drive at walking pace as there was a lot of oblivious pedestrians on the road. It sounded quite loud when in an enclosed space and when I went over a bump in the road it affected/interrupted the noise.