I have a problem and question with my 04 135 cdti ZTT auto 60,000ms. The question is, when I rev the engine I hear quite a loud whine in line with the revs. Is this normal and if so what is it?
The problem is that for some reason when I accelerate below 2000revs and the gear is still high (so the auto box hasn't changed down to account for the need to accelerate as I haven't done a kick down), the car struggles to accelerate smoothly and feels like it's pinking like in a petrol engine. Any ideas what this might be? I recently bought the car and fitted a Synergy 2 with Pierburgh maf, did the egr bypass (although with no gasket, fit a BMW pcv, and did the air intake mod. It seems fine when the car is cold, just seems to do it when warmed up and the gears change at lower revs.
I thought this was the Synergy, but I just switched the tuning bit off and it's still doing it. The maf switch is on. The Engine light has also come on, but again I thought this is to do with the Synergy as it came on a few days after I fit it and went off again when I changed the setting to 7 from 8. It has now come on again when running on 8 (more torque), hence why I tried turning off the tuning part today. The engine light hasn't gone out yet.
It also recently had a full service with filters etc. The idle is uneven and the engine rattles and is quite loud, although as I mainly know petrols, assume this is normal?
Pretty sure it was fine before I did the mods but it's always had uneven idle.
Hopefully someone can help me figure this out! Thanks!