I noticed in the garage there is 2 foot motor oil spray under my rear muffler, I figure this happens when I start my car in the mornings? Is this a sign that my carsound cat has already blown through? I am running stoich and have a catch can so why would oil be coming from my muffler...does high compression have anything to do with it? Thanks in advance

 

could be damaged piston rings or pistons.

 

Couldn't it be the fact that forged pistons will both rattle and not seal as well when cold?

 

What about timing......can that have anything to do with it? 3 weeks back my timing was set to 17 +12:1 compression my car was pinging like mad with 91 octane. So I retarded it to 12. Seems like after it was retarded I noticed the oil in the garage. I also did a compression test recently and had 260 all across the board. I am waiting on some RC 310 injectors but in the meantime my fp is at 50

 

daym are you serious? not a good sign at all.

 

its means its time to go h22

 

if you changed the timing, then you probobly fucked up your valves or just have fucked up piston rings or a piston is gone.

 

if it was a ring then how would I get 260 all across the board? Similar thin happened on my LS motor 6 months back and it turned out to be a gutted cat

 

to many hot heads here!!! you more than likely just have some moisture in your exhaust and when you start your car it is getting the black deposit at the end of your muffler wet and spitting it out. nothing to worry about? if your really concerned do a compression check and leak down

 

its your rings. mine does the same thing.

disregard the above, its just your rings.

sam

 

look im a tech.....there is no possible way to shoot oil out of exhaust. by the time it got to the muffler it would have burned off. it wouldn't even make it passed the valves because of burning in the combustion chamber. your car might be doing the same thing but you too obviously have no idea the cause of it

 

i'd definately have to agree, i've never seen oil come out of a tailpipe before, black smoke typically indicates running rich, blue smoke indicates bad rings, i guess if you were running like a foot of pipe out from the header, oil might make it that far, but most likely it is just water mixing with the black from the inside of the tailpipe. i'm no technician and i could be wrong, but i doubt it, and sure like to know if i am wrong so i can to myself

 

a friend of mine lost a piston in his 89 teg and when he would start it up he would have an oil trail behind his exhaust like you described.

 

simple solution to all these hairbrain schemes. you are running some 250-260 compression???! there is no possible way you have problems with rings or pistons. drive it like you stole it bud you have nothing to worry about besides the stains on your garage floor

 

exactly, it is probably just running rich since you reterded your ignition timing, put it back to how it was and see if it goes away, and if it does just retard it back to where you had it. No worrys brother


Rob

 

could be valve seals

 

people listen...yea his valve seals might be bad if thats what you wanna say but there is no no noo way he is spitting oil out of his muffler period. if you wipe your finger on thge inside of a muffler a black sut comes off on you finger (its a carbon deposit) when you start your car in the morning the exhaust is hotter than the outside air, it produces moisture that makes this black sut wet and it get spit out. it is not a hard concept to grasp. oh well to much effort on simple question.

 

Ummm . . . no.

There are only 3 ways oil can get into your combustion chamber:

- Blowby around the pistons/rings
- Through the valve stem seals
- Head gasket blown between oil passage and cylinder

Since you see it when starting in the morning my guess is that it is oil coming down from the valve stem seals. This is not uncommon in these motors. If it was blowby you would see it after initial startup since the oil would have to work its way up. The oil will drip down through the valve seal and puddle up on the piston.

The head gasket possibility is fairly remote. It is rare to see one blow in this manner.

 

just because it's a black fluid doesn't mean it's oil. It could be the moisture/condensation (that builds up from a cooling period) mixed with the carbon deposits within the exhaust system, and then gets shot out of the tail pipe when you start the car. This happens to my car from time to time, and I see this all the time at autocross events when you're on the grid parked nose to tail in a long line of cars. It can get pretty messy.


[Modified by Neo, 1:28 PM 5/28/2002]

 

That could very well be true. I made a mistake and assumed that he had confirmed it as oil.

 

It very well could be oil, in which case your analysis is right on target. I was just playing the percentages, which lean more toward the condensation issue.

 

My parents had the same problem with their Integra and what occasionally sprayed the back side of the car had the consistence of oil.