Shuddering/momentary "cough" while accelerating

**maca** · 11-04-2014, 10:15 PM

Back story:

Over two months ago, I unintentionally drove my car through some water. AAMI decided to replace the engine as it was hydrolocked and it was apparently the only component of the vehicle which has sustained any damage.

Before I got my car back, I requested VW conduct a full inspection of the vehicle (as the engine replacement had be performed by a non-VW workshop) and VW found that the injector plugs were loose. The tightened them up and I was happy to have my car back after driving rentals cars ranging from a Ford Taurus to a Toyota Corolla to a Fiat 500 to a Chevy Malibu.

Three or so days after I got my car back, I noticed a shudder and slight hesitation of power when accelerating, more noticeable when driving up hill. I took the car back to the assessment centre who instructed me to take the car to Volkswagen. After about two weeks, VW concluded that the mechanic (who performed the engine replacement) had drained the gearbox oil to determine of water had gone through the DSG and not topped it back up again. They noted it was only about one litre short of the recommended level.

On my way home from picking up the car for the second time, it shuddered again. It's been about 2.5 weeks now and while the shuddering is much less frequent, it's been replaced with a momentary "cough" interruption of power when accelerating under the same conditions mentioned above. It only tends to happen after driving for about 30-45 minutes. It happens just after the car shifts up and is about halfway through the power band.

Can anyone shed any light as to what it could be? I've had one mechanic say it could be the gearbox, another saying that one litre short of oil shouldn't cause any damage at all and I'm truly stumped.

Any help appreciated - thanks.

TL;DR: getting a slight cough/interruption of power when accelerating after changing up and about halfway through the power band.

**The One** · 12-04-2014, 12:21 AM

I'd just be pushing insurance for a gearbox replacement due to negligence of mechanic who fitted the engine.

**team_v** · 12-04-2014, 07:18 AM

It could actually be the injectors as i know the 125TDI's were having injector issues previously.
There is a whole thread in the Diesel section about it.

**maca** · 13-04-2014, 09:32 AM

Originally Posted by The One

I'd just be pushing insurance for a gearbox replacement due to negligence of mechanic who fitted the engine.

They've offered to fix it but I made an IDR activity due to the negligence of the primary mechanic, the insurance company responded saying that the vehicle is neither uneconomical or unsafe and they will be repairing it as originally stated.

Originally Posted by team_v

It could actually be the injectors as i know the 125TDI's were having injector issues previously.
There is a whole thread in the Diesel section about it.

I'll have a read in that section because it could be that. The only reason I would assume otherwise is because the vibrations became less frequent since VW topped up the gearbox oil.

**maca** · 05-05-2014, 07:47 AM

So and update for anyone who's interested:

My car has been at VW for almost three weeks now and when I phoned for an update, the staff member advised me that the gearbox mount was loose which was causing the shuddering. I asked if this could've been caused by water or even the engine replacement process and he said no, it's a totally unrelated issue. I find that hard to believe considering the car was perfect before the incident and the track record of the mechanic that performed the engine replacement.

On an unrelated note, the mechatronics requires replacing as well (second time I've had a VW with a fault mechatronics unit within a year). Does anyone have any information on what might cause the mechatronics unit to require replacing? As mentioned, the car was absolutely perfect before the incident and there were no knocks, vibrations or noises coming from anywhere in the car.

I still have an unconfirmed return date on my car - but I'm enjoying the practicality of the X Trail the insurance has provided me with (ignoring the lack of power and horrible fuel consumption).