Morning All,

Happy New Year.

I'm hoping to draw on the wisdom of this group again this week!

I've had an erroneous sound on my car since my ownership began and I can't place the cause so I'm hoping someone here may have experienced the same and could share thoughts.

Trigger for the noise is simple, cold or warming engine, shifting through early gears under 30%+ throttle seems to come in at the top of 2nd gear then drop away and doesn't return through the rest of the gears. It also intermittently replicates through kick down but not once the car is up the temp.

Worth noting I recently serviced the transmission and installed TransGo PR which has had no impact on this noise at all.

Any thoughts would be appreciated - I've looked over pulley items and all seem to be in good order. My fear is it that it could be something in the transmission but if I'm able to diagnose and replace some parts that would be amazing.

No current error codes to guide.

As always thanks in advance for any help.

Here is a video of the noise - https://www.dropbox.com/scl/fi/tuuid02hnwj91wmjvjfa1/XK8-Unknown-Engine-Sound.mp4?rlkey=db8s2i8428ccnelh7zjaa6nt4&st=csamc kn7&dl=0

Best,

Scott

 

Does it do it in normal and sport mode?

 

I can't hear anything on the video other than the normal engine/exhaust sound. If you operate the gearbox in manual mode using the J-Gate and hold it in gear, does that affect the sound?

Richard

 

Thanks for the quick reply.

Yes it does - the sport button doesn't seem to have any effect on the symptoms.

Scott

 

Thanks Richard

The sound is specifically between seconds 3-5 of the video. It sounds like a sudden build up of pressure somewhere. Interesting that you think this is just normal operation, maybe I am being too sensitive to the sounds of an older car?

I haven't tried manual mode but will test this and report back.

Scott

 

I hear it. It's bit faint, but it's a whine that gets louder and then disappears.

It sounds like it's in the trans. But if it goes away on warm-up it may not be worth pursuing. You've done about everything you can do to the trans, if you've installed the Transgo kit. Anything further will require pulling the trans and going in for exploratory surgery, as it were. Maybe best to wait until the trans truly needs a rebuild?

 

To close this one off I recently took the hit and had the gearbox rebuilt. Turns out the valve body top section had cracked and it was causing oil starvation in the gearbox. All back to new now, took a while to source that specific valve body, had to find a donor transmission.

Cheers,

Scott

 

Curious:- was the crack in the usual place?:

 

Thanks for updating us 🙂.

 

Very good question - honestly I don't know. Let me see if I can confirm with the tech who did the job.

 

Check the transmission fluid level..sounds like pump is starved of oil, Warm engine running car level