My engine had developed all kinds of knocking noises after the summer mostly lifter in nature. Once the head was pulled off there was lots of wear and I ended up fitting a practically Audi rebuilt head.
Now all is good with compression of 12bar across the cylinders ( 2 have 11.8bar) but there is still a knocking noise on idle once the engine is warm or once it has been thrashed a bit.
Engine pulls hard and is very lively. We thought a lifter may have been stuck so we did an engine flush and new oil 0w40 Mobil 1. Again all is good oil pressure 2bar on idle and goes to 3+ by 1500rpm moving out to 4bar easily.
We unplugged one by one the coil cables and noticed that once cyl 5 was without spark, the knocking goes away almost completely, while once the rest of the coil cables were removed the noise kept on happening.
My mechanic seems to think that this is a piston issue rather than anything else. He has seen it before happening in punto's where there could be pin damage or bottom piston wear.
Has engine encountered something like this before?
Now all is good with compression of 12bar across the cylinders ( 2 have 11.8bar) but there is still a knocking noise on idle once the engine is warm or once it has been thrashed a bit.
Engine pulls hard and is very lively. We thought a lifter may have been stuck so we did an engine flush and new oil 0w40 Mobil 1. Again all is good oil pressure 2bar on idle and goes to 3+ by 1500rpm moving out to 4bar easily.
We unplugged one by one the coil cables and noticed that once cyl 5 was without spark, the knocking goes away almost completely, while once the rest of the coil cables were removed the noise kept on happening.
My mechanic seems to think that this is a piston issue rather than anything else. He has seen it before happening in punto's where there could be pin damage or bottom piston wear.
Has engine encountered something like this before?
As steve says, propably rod bearing noise.
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