My 00 Si is burning oil, it burned about 1/2 to 3/4 of a quart in 2000 miles. My friend says it was blowing thick black smoke only in vtec. Compression is 190 185 185 155 after adding few drops of oil to 4, It got 165. What do you think the problem is? valve seals?


Modified by SimplyTron at 12:26 AM 6/24/2007

 

I would say rings are shot.

 

But if it was the ring wouldn't adding a few drops of oil to that cylinder bring the compression up drastically?

 

i'd like to know the answer to this question 2..

 

bump wity that question

 

Nobody?

 

does it smoke any other time, like when you first start the car or is it just happening when you are hard on the gas? And what is the mileage/history of the car?

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by SimplyTron &raquo;</TD></TR><TR><TD CLASS="quote">But if it was the ring wouldn't adding a few drops of oil to that cylinder bring the compression up drastically?</TD></TR></TABLE>if it was the rings you'd have shitty compression and the car would smoke. putting oil into a dylinder wont bring back the compression, a new hone and rings should do the trick

 

after thinking it over I think you need to replace your rings. The compression did go up when you added oil into the cylinder. Ususally if it increases, the rings are bad. If it didn't increase; the leakage would be around the head area (i.e. valve, valve seat/seal, cracked head)

 

Doesn't really smoke when not in vtec. The car has 84k on it. Every car Ive had if you add a little oil to the cylinder the compression will go up just a hair I guess its just normal wear.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by SimplyTron &raquo;</TD></TR><TR><TD CLASS="quote">Doesn't really smoke when not in vtec. The car has 84k on it. Every car Ive had if you add a little oil to the cylinder the compression will go up just a hair I guess its just normal wear. </TD></TR></TABLE>

Shouldnt smoke at all durring normal driving.

 

bump cause I burn oil when I get on it too. So i'd like to know an answer since it sounds like my situation.

 

I think the rule of thumb is, every cylinder should be within 10% of each other. After doing a compression test you add oil to see how much of a gain in compression u can get to know if its the rings that are at fault.

Cylinder #4 has really low compression and i definately feel confident to say thats its the rings, seeing that you got a increase when oil was added to that cylinder.

If you're still doubtful do a cylinder leakage test, it will pinpoint exactly where the leakage is coming from. Sound of air coming from the PCV or from the oil cap will comfirm that there is excessive blowby in that cylinder.

Rings and hone and you should be fine after...

 

Did another compression test today:
195 190 187 180
After adding a few drops of oil to each:
195 193 191 182

I don't know why it is normal now. Maybe I didn't have it screwed in all the way or maybe there is something else going on. I'm still burning oil though.

 

They always say. Do every cylinder exactly the same when doing a test. By adding oil to a cylinder and bumping it up i would be happy to bet the rings are worn. As most have said earlier.