Hello! Robin from Sweden here! I have some problems with my 2004 2.0 Jts SW 156.
I have just finished a repair including new belts, cam variator, inlet camshaft ( old camshaft was badly worn ), new inlet cam lifters.
The engine was week and made a rattling noise when revving ca 2000-3500 and keeping steady throttle before the repair. I was hoping the power loss and rattle noise was coming from the really bad worn inlet camshaft and/or lifters. The sound started to occur mild and has gotten worse in some months. When I discovered the bad sound the oil level was slightly low, it has been topped up since then. The oil used at this time was Mobil 1 5w40 fully synthetic.
But the bad sound is still there after this repair! The sound is very similar to that in this clip: https://www.youtube.com/watch?v=yTNxJHHXqwo
Therefore I'm starting to suspect big end bearings.. I haven't drove the car after the repair due to this bad sound. I don't want to make some more damage.
There is also a quite strong sound that reminds more of a classic lifters ticking/hammering sound at idle and raised rpm. The sound seems to be strongest in the area where the old inlet camshaft was badly worn, at cylinder 3 and 4. Examination shows that the new installed inlet camshaft lifters at cylinder 2, 3 and 4 feels spongy, you can press them down like a spring when the engine is tuned off. All the other lifters have a firm feeling and cant be compressed where they are. Its almost like the spongy lifters aren't filled with oil. Is this normal? Can it be a oil problem causing the lifters to sound bad and make them feel spongy considering that they are brand new? In that case, What could cause oil problem? bad oil pump, bad oil pressure due to worn big end bearings? Clogged oil passages?
Do you have any tips for how to further deal with this problem? Thanks!