Maiku64

OK found out more No compression in #2 cylinder and hardly any in #3 Mechanic says it is terminal Thanks for your replies

Thank you Unfortunately it is a holiday weekend and so I will have to just use my eyes for today Hopefully something obvious. Otherwise I will have to wait... Thanks again for the answers, gives my eyes direction.

I have a C5 LX 1749 cc (2001) While driving home late last night, I had to over take up hill. As I got to 50 mph it suddenly started to vibrate violently and become very sluggish on acceleration. Downhill would accelerate up to 60 mph, but uphill struggled. With the window open I could hear a very rough engine noise, reminiscent of old single cylinder motorcycles. This sounds like a misfire to me. Maybe only firing on one cylinder? As this happened under stress, is it more likely to be mechanical? I would be grateful for any ideas