Within the past few weeks my car has been burning a lot of oil and a lot of bluish smoke has been coming out the exhaust. I am running a test pipe and to an extent I know it's common for SOME smoke to be seen intermittently. Well I noticed it was more frequently and decided to do a leak down test. A friend in the area who also owns an S2000 is a mechanic and performed a leak down test. The numbers are as follows:

Cyl #1 - 10.5%
Cyl #2 - 14%
Cyl #3 - 8%
Cyl #4 - 5%


He said the motor was in really good condition so I'm confident it is. Just curious to why the excessive oil burning? I also cleaned out the PCV valve just for piece of mind.

I've never mis-shifted, oil always changed with redline 5w-30 every 3k miles, oil always checked at fill-ups. I'm running 4.77's also but I don't think that is the culprit. Car is an 02' with about 107K

Thoughts?????


****UPDATE 10-28-2009***

Well I did some documenting on how much oil I was consuming on a 2 week period. Basically I drained and filled my oil to the top of my dipstick at 107300 Miles. Drove around normally, spiritedly, VTEC often, highway driving, etc. I checked it every morning and at fill ups. Basically within a 1000 mile interval I have added 1/2 quart give or take. So I don't know. Another thing is I was also running my stock exhaust without resonator and a test pipe and switched that out and put my single exit on. I noticed the smoke was minimal and car ran fine. I read that having a sufficient battery charge was good to have on the leak down test and I actually had to buy a new one cause mine was dead about 3 days after I did the initial test.

So basically I am going to re test again properly and go from there. Car runs fine and oil consumption seems to be on par as a healthy running AP1.

Thoughts???

 

Anything over 10% is considered excessive. You've either got damaged valve seats or rings that don't seal. Given the oil consumption, most likely rings. Start saving for a new motor. They don't get better.

 

Are those wet or dry/cold test results?

Dry (the engine is relatively cold when the test is completed) results can look similar to your results. A proper leak down should be done after the engine is at least close to normal operating temperature.
I start with a cold test for reference purposes and that also allows me to remove the plugs when the engine is cold to get some fresh anti-seize on the spark plug threads. I then warm up the engine and conduct the "wet" test. I will typically let the engine sit for a few minutes to let it cool off slightly, pull the spark plugs and disconnect the injector clips, and then motor the engine until the oil pressure light goes out. I'll then begin the test, periodically motoring the engine over if I take more than a few minutes to get through the cylinders, and then repeat the test at least twice to get a good average.

The difference between a wet and dry test can be significant, and not just depending on the condition of the engine. Dry/cold leak-down tests can vary greatly from test to test depending on several things to include the amount of residual oil on the cylinder walls to the relative humidity that day.

My most recent test results at ~60k miles were:
Dry/Cold: 1 - 3% 2 - 2.5% 3 - 2.75% 4 - 2%
Wet: 1 - 1.25% 2 - 1.5% 3 - 1.5% 4 - 1.75%

The previous dry results were not consistent, however the previous wet results were identical. The previous test was conducted at ~50k miles. I've had 4.57 gears installed since around the 22,000 mile mark.

 

The 4.77 gears do contribute to engine wear. RPM really means "ruins people's motors" (a quote from the "Old One" at Endyne).

Compare the RPM in every gear - your car to stock, and then consider how much more wear is being done.
Your oil's life is not based on how many absolute miles you drive, but how many cycles per mile your car experiences - or RPMs per mile your car averages.
A stock AP1 will see about 3750 RPM at 70 MPH, your car probably sees closer to 4390 RPM at 70. That may not seem like much, but it is - especially when you consider that you're essentially cruising around in what would be 5th gear in a stock car.
If all your miles were in 6th gear - your car would be seeing basically the equivalent of 3600 miles for every 3000 miles of stock driving. Realistically, that would be a lot closer to ~4100 miles under normal driving conditions with a reasonable split of highway and city driving. Those 4.77 gears take their biggest toll in the lower gears. If you track your car a lot - the wear factor is greatly increased.

 

All leakdown tests should be done with the engine at operating temp.

 

The leak down test was done at normal operating temps. The car runs fine. No hesitation, bogging, stuttering, etc... still pulls through VTEC. So I dunno....I guess I just need to monitor and chart how much oil I am actually consuming to get a better idea and take it from there.

 

14% is on the high side. My tester says anything up to 10% is ok. Large variation also indicates something could be bad. Check the valve retainers for cracks. Also, during the leakdown test, you should be able to spot where the air is leaking from

 

consider switching to a 40 weight oil, which is one of our optional oil choices as per the owner's manual. Try Castrol's 5w-40 as a test and see how it works for you, it's a cheap test. I bet it will consume less than the Redline for you.

You might also have sticky oil rings, a treatment like Auto-rx is a good way to free stuck oil rings and can restore oil control in an engine. Auto-RX is an inexpensive oil additive that has an excellent reputation in the oil enthusiast industry, well respected over at www.bobistheoilguy.com forums. One of the few products that does what it reports to do.

Lastly, put in a new pcv valve rather than cleaning the old one, for 3 bucks it is the way to go.

I think trying a few small things like this can help reduce your oil consumption problems so long as your engine is really messed up. Small investment for the possibility of helping your situation.

 

Valve retainers we're checked and fine at my last valve adjustment at about 6k miles ago.

I'm thinking of just switching to a 40w and going from there. We checked for leaks and there was a slight bit coming from the dipstick area. Nothing from the coolant lines, exhaust, etc....

 

perhaps your valve guides are worn.

i would take the head off and get the head inspected and do head work if necessary, like relapping the valves, new valve guides...new retainers/keepers.

then do the leakdown again and see where you're at.

if it's still bad...it's probably the piston rings, and you'd only have to save up for the short block