m44 Engine Issues But I need Hardcore help

[J10B]

I get a CEL saying I need to replace the 02 sensor, I replace. 3 4 days later CEL comes back on. My GF drives this DA supercharged Z3, and she says she doesnt notice a loss in power. Well I am thinking of selling so i take it to the dealer to get this issue looked at. They end up doing a compression test and say there is 80% leakdown from Cylnder 4 into the crank. Heres my problem. The car drives, and it is fast. The car has NO SMOKE. Nor did it ever, so if that is the case HOW TF is the cylinder 4 toast.

[stimpee]

Originally posted by J10B
I get a CEL saying I need to replace the 02 sensor, I replace. 3 4 days later CEL comes back on. My GF drives this DA supercharged Z3, and she says she doesnt notice a loss in power. Well I am thinking of selling so i take it to the dealer to get this issue looked at. They end up doing a compression test and say there is 80% leakdown from Cylnder 4 into the crank. Heres my problem. The car drives, and it is fast. The car has NO SMOKE. Nor did it ever, so if that is the case HOW TF is the cylinder 4 toast.

Get a second opinion/another compression/leakdown test done. Something sounds a bit funky...

Steve

[myred318i]

J10B.... what is up with all of these panicky threads about your car engine being all f@#%ed up?!

Damn, last week you said that your DA S/C caused your engine to blow, http://www.bimmerforums.com/forum/sh...threadid=42264 then... you take it in and maybe it's not, then this morning you're puttin' out a feeler to sell the car and the DASC unit - Separately! http://www.bimmerforums.com/forum/sh...threadid=42218 http://www.bimmerforums.com/forum/sh...threadid=42933

Now you're basically restating the problem in another thread..:atom

If your car went berserk, I'm really sorry.... but you're wrapped too tight. Relax, get some expert advice from someone who can actually see, listen, and work on your car. Don't keep sending up these flares 'cause I'm starting to think you're the one with the leakdown!!

[J10B]

dude u haev a 318i there is a GP for DA unit I am trying to figure out WTF happened here so people do go buying a blower that gonna @#$% their engine, add that to the fact that noone responds......

[Kos-motate139]

It's possible that your engine could run perfectly fine with a lot of leakdown.

Now let me define 'perfectly fine'...

When I bought my 2002tii, I got it for a steal, so I didn't have it thoroughly checked out. It ran fine, pulled strongly up hills, and I drove it probably 10K miles before I had it looked at by someone that knew what they were doing.

The #4 cylinder and cylinder wall was totally scored. The only real way to tell something was wrong was some oil being blown up the crankcase's breather tube into the air intake, and the tailpipe sniffer could tell something was very wrong. I don't know what the leakdown % was, but it had to be pretty high.

Now I'd assume that a newer engine would have serious problems with a bad cylinder, but it could be on a par with the problems you're having, not sure. I'd say it's definintely time to crack that puppy open and see what happened.

[J10B]

I did my own leakdown again.
Dry
1. 190
2.170
3.185-190
4.130

Wet
2. 200
4. 150

Could it be a bent valve? in 4 and 2?
I havent seen ayn oil in the air filter but I do have some in the PRV valve area.