Hi all,
I have a 2007 C4 diesel w/ automatic gearbox (w/manual mode) 284K kms.
Sometimes when I get to about 2800-3000 RPM, the car momentarily loses power for usually 2-3 split-seconds, and the revs go up each time before recalibrating.
I tried putting it in manual mode, and it happens much less, but still can happen up hills or when it seems like the car would naturally attempt to switch gears if it was in automatic. It seems to almost always happen in 5th gear.
I also tried revving it in neutral, and when I push it to 3500 rpm or so, it loses power continually and pops up with "gearbox faulty."
I took it to a mechanic (very good reputation and works on automatic transmissions - hard to find here in rural Portugal) who told me it's in fact the automatic transmission. Honest guy, he says if it's his car he would not fix it because manual works fine and the repair is expensive. (OK - manual MOSTLY works, but still makes me a bit nervous when I feel the power slip once in a while.)
Like I said the shop has an excellent reputation and he seems to know his stuff. I have occasionally noticed this issue in manual mode, and I'm confused that if it was a downshifting issue, why it would still happen in neutral. Can anyone please explain this - or do you think I should get a second opinion? (Or get the gearbox fixed...)
(Other context - maybe of consequence, maybe not - I recently had the battery, serpentine belt, and timing belt replaced as part of routine maintenance. The mechanic checked that these were all OK.)
Thank you!!