Cain74

Did you buy it from North Coast? I thought the sold it at auction to Prestige. The one at Prestige was the same VIN at least. The guy at North Coast told me that they replaced the coils and still had the problem. That is when the did a compression test and found cylinder #2 as bad.If this is the same car, let me know what you find. Good luck.

somedude_001

yeah I bought it from prestige. I will keep you posted. They are dragging their *** getting me a title. I will not start diving into it until I get one. The car is here with me in buffalo, and 3 different times they told me they sent the title and I still don't have one. I am not sure what is going on but a call to a lawyer will happen in the next couple days if it does not show up. I can't sit on broken cars like this.

JohnnyJ A6Q

That North Coast replaced all the coil packs and still had a problem, and after more investigation they found that cylinder #2 had a low compression of 75 psi, did you see this thread before you purchased said vehicle ?
Or did North Coast pull a sleaze ball move and dump it at auction, But now as I type this, I recall you stated that you thought it was coils, so someone told you of the miss, the thing is if north coast did not reveal a known engine defect such as low compression on #2 as documented here, and Prestige purchased it at auction not knowing of engine problem, then Prestige should go after North Coast through arbitration at auction house, and bring these posts to prove time frame and the fact that north coast knew of low compression....

somedude_001

Issue is resolved. There was a rocker arm with minor damage. I have to imagine it was a manufacturing issue with quality control. I replaced the rocker arm and the lash adjuster. The total for the repair was 50 bucks. She purrs like a kitten. It still amazes me how incredibly fast this car is. I did not run a compression test but I did check leak down and I got 17% on cylinder 1,2, and 3 I didn't check anything further than that because the missfire was only on cylinder 2

03_AR_CO

I would sure like to know where a rocker arm was found on a W12 engine, show me one on a 4.2 and I'd be amazed too. Just sayin

Giovanni Giovino 6.0+6.0TT

Pictures of W12 "Rocker Arm", these rockers do pivot on the cam lobe with the valve spring on one side and a hydraulic damper on the other side, so it is a rocker.

MP4.2+6.0

Having worked on the only one in "classic" format, I get what he meant. Old school rockers haven't been seen since the mid 60's S90 and then the early 70's 100LS slant inline 4. Solid tappets, hollow push rods, individual rockers on separate shafts, dual valve springs, cam in block simple chain. Set the valves with feeler gauges with valve cover off warm. But valve stem tips that would break with the direct mechanical load, crap head gasket between early design alloy flat combustion chamber head on cast iron block, cooling system almost designed to have problems. Given flat head, two valves out to full combustion chamber width, and all mechanical valve train, about as "interference" an engine as you could imagine. Even with its tractor origins, motor found its way with an OHC head switch to the 924. Along the way the tooling had passed to AMC and sorta same motor was in the Wayne's World Pacer in 4 banger form. But, the last of the old school bolt down individual rockers from Audi.

03_AR_CO

Well, I do stand corrected, I have never had the valve covers off of my W12, just really had no idea it was setup that way, I am surprise a bit to see it. Looking at it makes sense though to time the valves with the offset cylinders.

Giovanni those are very interesting pictures. Are they of your car? If so what was the tear down all about?

Thanks

Giovanni Giovino 6.0+6.0TT

Hello 03 AR CO,
Yes they are of my vehicle, but not my A8L W12, but my Bentley GT, see my rebuild in the link below.

My GT re-build in pictures !! - 6SpeedOnline - Porsche Forum and Luxury Car Resource

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born_slippy

Hooooly crap that Bentley rebuild must have taken you all weekend. And here I am hemming and hawing over a simple strut replacement.