Hello everyone. I am Marc--haven't posted here other than in the registry--I have 61979, an 03 Stratus/Crema Z8. Fabulous car; I've had a ton of fun with it--now has about 105k miles on it and the engine still has that edgy, crisp quality about it, but now I'm worried.
For about a year I've been having 'service engine soon' light issues. The BMW dealer has addressed it, said it was "a valve", charged me a couple hundred, and the light came on again soon after. I flirted with a local independent garage; someone told me they were capable. When I asked them if they were comfortable working on the car, they said "sure, we sent our technician to train in Germany". Frankly sounded no worse than what you really get at the authorized dealers--from what I can tell, one guy who who went to Munich and 20 screwdriver mechanics who can change parts. They kept the car a couple days, and when I came back it was on a half hoist with a sheet of paper downloaded from the internet under a wiper on the windshield. They said it was either a $50 valve, or else a condition of carbon buildup (I think in the intake ports of one of the cylinder banks). If the latter, would require R&R of the engine.
I passed on the work, and have simply enjoyed the car for a full year, about 6k miles. In that time, the car has always run fine. The SES light, which they turned off at the independent garage, came on a few weeks later. The light stays on about a month, then goes off for about two weeks, then comes on again and repeats the cycle. Actually, the light has now been off for about two months. The car also had no problem passing its CA smog test just a couple months ago.
Now due for routine service, so I had my BMW dealer query the codes again. They are telling me that it's the carbon buildup thing and they need to pull both heads, send them out for de-clogging, and put em back on. $15,000! Also one of the catalytic converters needs replacing, they say--$3600 for that.
Now, there's just something wrong about spending $20k to repair a car that runs fine. Also, I am loathe to recondition the top end of an engine with over 100k miles on it. As I said above, the engine is still crisp and edgy. While I really like my service manager at the shop, in the past, I've had to scream at him because the technicians did sloppy work, and I can assure everyone that this is not some discount shop--authorized BMW dealer charging serious money. Given my past experience, I'm fine with these techs changing external parts like the starter motor ($1500 for a rebuilt one), AC compressor (same), etc. But to pull the heads?
Is this a common problem on Z8s/contemporary M5s? Any ideas?
Thanks!