I'm hoping some of you will be able to help me as I'm fearing the worst (knackered piston rings). I bought the car in December and the first week of having it I noticed a slight shake at idle, after idling for 10 minutes the EML started flashing so I got my OBD/II scanner which pulled P0300 & P0301 codes (random multiple misfires & misfire cylinder 1).
The car itself seems to drive fine though I'm beginning to suspect that's the turbo masking the lost cylinder and the EML only ever flashes at idle, as soon as it's under power it seems to sort itself out. I changed coils and plugs, problem persisted. It's a start/stop model whose function has never worked, presumably due to misfire. The timing chain is a little rattly for a couple seconds on first crank at cold start which i'm guessing is either oil pressure or tensioner. It recently had a relative compression test done at a local garage and found ~90psi cylinder 1, ~110psi cylinder 3 and 140-150psi cylinders 2&4. The garage didn't perform a leak down test but I would imagine that it's piston rings as typically head gasket would be adjacent cylinders rather than alternate (I think) and a burnt valve would be blowing blue exhaust? Just plugged OBD in today and it's now pulling a P0343 indicating cam sensor high signal which I wondered about cam sensor before having the compression test done although I believe that code can also indicate the timing is off which it appears to be.
The car's only done around 68k so seems mechanically very young for piston rings to go. I'm wondering what my options are now? Is there any point doing a leak down test? It seems to be cheaper to have the whole engine reconditioned than just the piston rings changed and I unfortunately don't even remotely have the skills necessary to do a bottom end engine strip myself. I've got copies of both the PSI readings and 2 "picoscope 6 automotive" graphs (that I can't actually decipher) if that helps. Any help/ideas hugely welcome, cheers.
The car itself seems to drive fine though I'm beginning to suspect that's the turbo masking the lost cylinder and the EML only ever flashes at idle, as soon as it's under power it seems to sort itself out. I changed coils and plugs, problem persisted. It's a start/stop model whose function has never worked, presumably due to misfire. The timing chain is a little rattly for a couple seconds on first crank at cold start which i'm guessing is either oil pressure or tensioner. It recently had a relative compression test done at a local garage and found ~90psi cylinder 1, ~110psi cylinder 3 and 140-150psi cylinders 2&4. The garage didn't perform a leak down test but I would imagine that it's piston rings as typically head gasket would be adjacent cylinders rather than alternate (I think) and a burnt valve would be blowing blue exhaust? Just plugged OBD in today and it's now pulling a P0343 indicating cam sensor high signal which I wondered about cam sensor before having the compression test done although I believe that code can also indicate the timing is off which it appears to be.
The car's only done around 68k so seems mechanically very young for piston rings to go. I'm wondering what my options are now? Is there any point doing a leak down test? It seems to be cheaper to have the whole engine reconditioned than just the piston rings changed and I unfortunately don't even remotely have the skills necessary to do a bottom end engine strip myself. I've got copies of both the PSI readings and 2 "picoscope 6 automotive" graphs (that I can't actually decipher) if that helps. Any help/ideas hugely welcome, cheers.
