Evenin all. Took my car in to a local garage for 2 tyres and an oil and filter change. After the change, the engine was great! a lot quieter, and pulled better.
However, a few days later, i started the engine in the morning, and noticed that once the revs settled to there usual 750ish rpm, a loud vibration could be heard from the engine. Popped the hood, and the sound appears to be coming from the rocker cover (i have the plastic cover removed - ongoing issues with splitting turbo boost hoses!) I got back in the car and pressed on the pedal slightly, to raise revs to 950rpm, the vibrating dissapeared, but a rattle can still be heard.
Also the idle isnt smooth. every second or 2, you can hear the engine miss slightly, not a full misfire, but a partial, and there is a faint 'bump' felt in the car. Once the engine is warm, the missing dissapears, but the rattle can still be heard at idle.
Now to the oil level, When i had the car back, i checked the oil level, saturday morning, flat level ground, engine off for 12hr+ The oil was just on the max line (this was before the rattle)
Now, the oil is about 8-10mm ABOVE the max line (0.4L?) when checked in the same way.
Now the sump is 5.5l, but the garage said they put a full 5l can in, so it should read halfway between the max/min lines
And before you ask, no oil in the water, and no white cream in filler cap
I'm thinking cam chain/snapped lifter/blocked injector?
PS, car is 2.0DTi, 96k 2003 model