Ford C-MAX - Ford Cmax wobble under acceleration - si5000

I have a 2007 Ford C-Max 2.0 petrol Automatic.

It has a wobble but only on acceleration. You feel it through both the accelerator pedal and through the floor in either of the front seats. As you ease off the throttle the wobble goes away and the car will cruise along nicely. This leads me to think it's something drivetrain related..?

So far we've tried the following through two different garages who have not been able to solve the problem:

4x wheels balanced

4x wheels aligned / tracked

4x new tyres

Wheels swapped front to back

2x new driveshafts (offside and nearside both had play in them) and CV joints

2x new front wishbones (rear bushes were failing)

2x new differential bearings (gearbox was removed and checked over and given clean bill of health after new bearings).

Having now spent a fortune trying to repair this car I'm now at a point where it might be time to take a huge loss and scrap it. I can't afford to keep throwing money at something we can't seem to fix. Any other final thoughts?

Ford C-MAX - Ford Cmax wobble under acceleration - Railroad.

My first thought would've been a drive shaft but you've eliminated that, so next I would suspect a worn or broken engine mounting.

Ford C-MAX - Ford Cmax wobble under acceleration - si5000

Yeah that had crossed my mind and I have mentioned this to both garages, but neither have confirmed it as having been checked.

They've both simply stated that mechanically they can't fault it now - helpful as it's clearly not solved the issue.

To be fair, having had the driveshafts replaced improved the problem a LOT! Just not a total cure...

Ford C-MAX - Ford Cmax wobble under acceleration - Peter D

Engine or gearbox mount failure. Regards Peter

Ford C-MAX - Ford Cmax wobble under acceleration - JONATHAN_11_80

This sounds like an engine mount issue, the top engine mount is a common failure point. The lower engine mount is more likely to cause this issue. As it controls engine movement on acceleration. However I am surprised this hasnt been checked if the gearbox has been removed.

Ford C-MAX - Ford Cmax wobble under acceleration - gordonbennet

Were the inner CV joints changed? if not i'd try repacking them with grease and see if it improves.

Also check there isn't a secondary inner drive shaft on one side with its own bearing.

Ford C-MAX - Ford Cmax wobble under acceleration - si5000

Inner CV joints were changed, it was one whole assembly with the new driveshafts.

Will ask about any additional inner driveshafts

Ford C-MAX - Ford Cmax wobble under acceleration - gordonbennet

Has your mechanic, i presume someone is doing this for you, tried putting the car up on a lifter with dropped wheels, then with it in a high gear and someone inside driving it have a good poke nose see what's going on underneath, the problem if its drivetrain related might show itself but obviously there will be no engine load to speak off.

A rolling road might be another possibility but its going to be almost impossible to see underneath except by use of mirrors and lights, though if it is an engine/gearbox or suspension top mount problem with the bonnet lifted it might reveal itself.

Edited by gordonbennet on 11/03/2017 at 08:46

Ford C-MAX - Ford Cmax wobble under acceleration - Wackyracer

As you say you feel the wobbling through the floor, have you checked or changed the Anti roll bar bushes. When they used to fail on some Toyota's like I had it felt like someone was hammering on the underside of the floor with a rubber mallet.

We had a truck at work that used to have a strange vibration at full throttle and that turned out to be a blocked fuel filter. It was a rental truck so was one we couldn't blame our own garage for.

Ford C-MAX - Ford Cmax wobble under acceleration - si5000

Minor update on this:

I asked the garage to do a through check of all of the engine / gearbox mounts. They said that whilst looking their age (10 years old and 70,000 miles) none looked in a particulary bad state.

However I asked them to change the upper engine mount which has not solved the issue.

The lower gearbox/engine mount should be changed today (as the supplier sent the wrong part yesterday)...but garage do not believe this will have any effect either.

Ford C-MAX - Ford Cmax wobble under acceleration - si5000

Further update, the garage rang, they've changed the lower engine/gearbox mount, but say that this has not fixed the problem.. :(

Ford C-MAX - Ford Cmax wobble under acceleration - RS2016

Could this possibly be an electrical / electronic fault? Could something be affecting your car's:

  • ABS?
  • Electronic Stability Control?
  • Electric steering (if fitted)?
  • Engine Management?
  • Auto Gearbox (if fitted)?
Ford C-MAX - Ford Cmax wobble under acceleration - Richard Cross

Hi I have the exact same problem did you manage to fix yours

Ford C-MAX - Ford Cmax wobble under acceleration - Geoff Briers

I have the exact same problem, 2007 CMax 2.0Auto Petrol, mileage is about 44,000

So far we've balanced the wheels, adjusted alignment/tracking, replaced both driveshafts, replaced all engine and gearbox mounts. When the driveshafts were replaced the problem was very much improved, but definately not eliminated. The old driveshafts did have some play in them.

My mechanic has run out of ideas. the auto box appears to work normally, but we're now beginning to suspect maybe we have a fault in the auto box which has been causing the problem all along.

Don't really know what to do next. Just drive it till it shakes itself to death? Take a hit and scrap it?

Ford C-MAX - Ford Cmax wobble under acceleration - Markshark2020

Hi I know this is an old thread but did you get it fixed if so what was it? As we have the same issue and have tried everything. Thanks mark.

Ford C-MAX - Ford Cmax wobble under acceleration - Markshark2020

Did you find out the issue as we have the same issue have tried all we and machanic can think of ? Thanks mark