hammerj2

Just like the title says, my 00 si burns oil at idle as well as low rpms ie fitting in traffic produces a huge cloud of blue smoke. It burns roughly a quart every two weeks. Car is built running 24 lbs of boost. compression ratios are good. Haven't done a leak down. 25k on the motor and 5-10k on the turbo. Any ideas?

neek175

Check catch can / pvc system I had the same issue and that was the cause in my situation.

Alfa Turbo

Could also be the rings. You can have sealing issues and idle yet still have a good seal at higher RPM's. Compression test followed by a leak down IMO.

Good luck.

hammerj2

thanks for the help. can you please elaborate on the catch can/pcv setup. i am currently running a catch can, and there is some blow by, which worries me a little.

machine4321

could be valve seals. if it was rings it would blow oil all the time. Also your turbo might be giving you a heads up

blackeg

ive had these symptoms twice in the past few years. both times it turned out to be the turbo. make sure you are running and oil restrictor and that your return line looks good.

builthatch

OP, what happens if you accelerate lightly in 3rd or 4th gear until the rpms are in the 3500-4000 range, hold it and let off, so it goes deep into vacuum...then gradually tip back into the throttle? do you see a puff of smoke at any of those moments?

Alfa Turbo

Not so. At idle there is less pressure on the rings and you can get blow by... at higher rpm and pressure the rings will seal. Not definitively saying this is his issue but it IS one possibility.

Tjabo

I've got this going on too. . . My drain has a -10 (or -12?) 90 degree elbow at the bottom, so it could be an issue of my drain being less than optimal, but it's an intermittent problem, my engine is old and tired, and my turbo is new. I had the same exact deal with my previous turbo on, and it was also in perfect shape.

I think I'm going to do a compression test and leakdown at some point when I'm a bit less lazy. . .

Oh yeah, and I've recently replaced my valve seals when I put in some Brian Crower springs (which are sweet). No wait, maybe that was only when I put new springs on the other engine. . . Maybe I didn't put them on this one. Hmmmmm. . . Nevermind.

neek175

How do you have it configured?

rev-speed

any pressure or smoke from the valve cover breather tube?
is there oil in the pvc hose?

Tjabo

Hey guys, I did a compression test and tried to do a leakdown tonight. I really am at a loss as to whether these results tell me anything or not. . .

My compression tester has always read low, and my results tonight were:

142 144 142 144

Seems okay for what I've seen in the past with this tester on healthy engines.
But here's the problem, embarrassingly, I have to confess that I've never done a leakdown test before. It Harbor Freight Leakdown Tester with the regulator cranked all the way open. Then, as I started cranking the regulator in, the percent gauge (closest to the cylinder) wound around toward 100% to the "set" point.

For each cylinder, the left gauge (pressure) read only 14.5-15psi when the right side gauge was at "set".

The escaping air was clearly going past the rings, as it was only coming out of the dipstick tube, which was the only place I listened to the crank case. The valves seemed well sealed, as the exhaust and intake were both quiet.

So I guess the question is whether, from these results, it is possible to determine whether the rings are all shot to almost exactly the same degree, in each cylinder, and that is where the oil is burning. Or is it possible to tell from these results that the rings are great, since the results in all the cylinders are all the same?

How the hell are you really supposed to use a leakdown gauge? It makes no sense to me how I could get a useful percentage of leakdown out of this gauge. . . . . .

One interesting thing I have to resolve next is that on my last oil change, I got the sucker about 1/3 quart over full. I'll have to take a half quart or so out, and then see what happens. My oil burning at idle is kind of intermittent, so I don't know as I can say the drain tube configuration could really be to blame or not. Hmmmm.....

EDIT: Oh, my plugs look perfect. I'm thinking all of this together probably means in my case that the oil is not getting burned in the cylinders because of the rings. If fixing the overfill doesn't take care of it, then I think it's time to give the drain configuration some attention. Anyone?

Tjabo

Okay, I found a nice little video on Youtube that shows how to do a damn leakdown test. . . Since I might not be the only one on here who didn't know how to do this correctly, here is the video:

http://www.youtube.com/watch?v=4HYdaxxas4Y

Now I should be able to re-do my test and figure out where I'm at with an actual measurement.

Kyle R

iTrader: (1)

Tjabo

Okay guys, since I'm having some of the same symptoms as the OP, I figure I'll keep posting up my analysis process for my problem in case it might help him keep from doing some of the same dumb stuff as I am!

Anyway, since I was able to see on Youtube how to actually use this Harbor Freight Leakdown Tester, I re-did my tests when i got home from work, although this time the engine was cold. I'll have to do it again with it warm some time.

The results are:

1-18% 2-15% 3-18% 4-17%

All of these leakdown rates appear to be good, and the lower leakdown rates seem to correspond with the higher compression numbers.

Correct me if I'm wrong, but I think what this is telling me is that the bottom end of my engine is pretty healthy? In that case, I'll take a half quart of oil out and see what happens. If that doesn't fix it (which I'm guessing it won't), then it's time to address my oil drain situation and make that a bit more optimal.

Sound right?

Tjabo

Hammerj2, how you coming with this?

For my part, I've done a little more diagnosis, and still have the problem. I did a hot leakdown last night after checking to see if the problem still existed, and basically I'm at about 15-17% leakdown. That seems pretty good to me, so I'm thinking oil probably isn't getting past my rings. Wipe that one from my list.

This problem is definitely worse since I have put the 20w50 oil in a few days ago for the warmer weather.

As I mentioned before, the dipstick was indicating that the oil was over-full, so I took a half quart out. That put me at about the halfway point in the acceptable range on the dipstick. The problem is not reduced.

All of this in conjunction with the fact that the problem seems to be exacerbated by thicker oil makes me think it is a drain problem. I have a -10 90 degree fitting into the pan, which I see the Shodan has said is an absolute "no no."

The next thing I'm going to try then is to open up the bottom of the drain some by getting rid of that 90 degree AN fitting. After that, if the problem still exists, I'll address the top of the drain, although I'm pretty sure that is real good and open. . . .