Hi all - driving along happily in my 996 C4 last month when out of nowhere the dashboard lights up and it starts misfiring. 78k miles and I only bought it last October, having driven 3k miles since then. Had it towed to a local specialist who confirmed misfiring across three cylinders, and advised it needed a camshaft solenoid. Unfortunately upon further inspection they noticed no compression in one cylinder which seems to have stumped them. They're now advising it's an engine out job to do some further investigating before they can accurately diagnose, with an estimated cost of £5k-£8k depending on what needs doing...although that's obviously not guaranteed until they find out what's going on in there so it could be more. They did also offer me £7k for the car as is, which I politely declined. Has anyone experienced anything similar, and can you share any advice? This garage is a Porsche specialist so presuming they know what they're talking about, but if there's any way I can avoid the massive bill then I'd like to explore all avenues where possible!! Thanks!
2001 996 C4 - Specialist is stumped (misfire and no compression on one cylinder)!
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YOUR RESEARCH2001 996 C4 - Specialist is stumped (misfire and no compression on one cylinder)!
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I've never heard of loss of compression on one cylinder other than a cylinder liner failure (D chunk) but that would be more obvious. I would have a word with Hartech to see if they have any ideas. They are the main rebuilders of M.96 engines, and have more experience than anyone else.
Long shot it's not a cat blocked happen on my wifes old Z3 no power missfire
HI James Going back to basics, If the is NO compression then logically it can only be valve or piston related, my guess would be a broken or seized valve, If it was a timing chain issue tensioner, skipped tooth etc that would affect more than one cylinder. As per Richard Hartech are the guys for engine repairs, well worth a call. Good luck Andy
Thanks guys - spoke to Hartech, who advised the engine defo needs taking apart to diagnose...fingers crossed it's nothing too sinister! ??
Sorry to hear that, it will be expensive taking it apart might be cheaper if not planning to keep long term to put a used engine in from a breaker. All the best
Hi I know this is a while ago but did you ever sort this low compression issue on one cylinder?
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