Dear People Smarter than Me,

On Saturday I partook in an AutoX event in MA, the car ran fine (and I dominated the Novice class, based on the unfair way the classing works). I have a ~90 mile trip home and there is a relatively small mountain on the way to my house, about 8.5 miles away.

Approximately 0.5 miles up the slope, my Evo is in 6th gear, heavy into the turbo lag, but I don't downshift to keep my speeding to a minimum. Suddenly a thick white plume of smoke and/or steam fills all my mirrors. I pull over and kill the engine in a panic. I pop the hood, check my fluid levels, all normal, and verify that the coolant temperature is normal too, it is. I call a knowledgeable friend, who suggests it may be a blown head gasket and I might as well just drive it home since any damage has already been done. Another half mile up the mountain it does it again and this time I stop, leave the engine running, and sniff the exhaust. It does not smell like burning oil and does not smell strongly of coolant if at all (I may have been psyching myself out and smelling a slight twinge of coolant that wasn't there). The rest of the ride downhill and all the way home there is no further incidents with any smoke or steam being emitted from my car.

Upon arriving at home, I check the fluid levels again and perform an oil change. Fluid levels remain normal and the oil appears to be free of coolant, but is quite dark in color. The oil change was 1500 miles and several AutoX events old, it seemed to be ok (color-wise) when I checked it before the event. In the intervening two days I have been unable to get the car to duplicate the incident, despite my best efforts to mimic the loading conditions on the engine without returning to the original site (mountain). I plan on making another trip out there next chance I get to see if I can get a reaction from the car. On a whim I am having a compression test run on the car tomorrow, but I doubt it will reveal anything abnormal.

About the car:

2006 MR
27100 miles on the ODO
Mechanically stock, except for a newly installed Perrin complete turbo intake
Car has been tuned by The Shop in Norwalk, CT (Junior)

I greatly appreciate you reaching the bottom of this lengthy post as well as any information, suggestions, or feedback you may provide to me.

Thank you,

-Bryan

 

Can you do a compression and leakdown test? You checked everything else, so why not.. Post up the results.

 

I just had a compression test run today (my shop of choice in town did not have the capability to perform a leakdown test). I question the results and will probably buy my own tester and try it again...the results are as follows:

Dry Wet
1 110 110
2 115 120
3 105 105
4 100 110

I made it out to the site of the problem the first time and gave it another go. This time the smoke was less voluminous and looked like burning oil. It had the blueish color to it. I don't know what the deal was the first time, it may have been a combination of the old oil, the tint of my sunglasses, and the position of the sun or something...

This result now leads me to believe that the turbo may be consuming or leaking oil when it is lagging and going uphill. Does that make sense? Does the turbo work harder at lower engine RPM going uphill (6th gear) than when it is spooled up (say 4th gear?). Alternately is it running hotter (less convective cooling)?

Thanks,

-Bryan

 

Check your upper intercooler pipe. Maybe its loose. I had a scenario almost like you but I was going about 70mph flooring the gas pedal and all of a sudden there was a gush of moisture that came out from the vents and got on my window. I pull over thinking something bad had happen. After checking everything, the clamp was loose on my upper intercooler pipe and there was a big leak. I was glad it was just that. So just check your clamps on your pipings.

 

I will double check the clamping, but I have no loss in power, nor do i suspect a boost leak. The smoke only appears to be coming from the exhaust and only when lagging up that one steep slope.

 

At low rpm and high load you could be running extremely rich. What did junior do for your part throttle tuning? Sometimes the cars can be awesome in all normal driving conditions and not so hot in those 1% outlier situations. Can you log AFR or read a gauge?

 

I do not have the capability to log AFR at this time, but the car running really rich makes tons of sense. That would explain the white cloud.

I unfortunately do not know what Junior did for part throttle tuning. I ended up leaving the car at The Shop overnight and didn't get back there (1.5 hours or so) until after it was already done the next morning. I have a whole bunch of questions that I plan to ask next time...

 

Running extremely rich would cause a black smoke, not white as you described. Black smoke = rich, blueish/white = burning oil, white = coolant. Those compression results between the wet test in cylinders 2 and 3 is troubling. That is right on the limit of suspected compression problems. I always abide by the 14-15psi rule for issues. Anything greater than a 14-15psi difference and there is an issue, not always major.... yet. You checked the coolant reservoir for any changes in color? Sometimes oil can seep into the coolant and thus it is much easier to check, just take a look in the radiator. You have never had any overheating problems with the car, right? You can try and do a boost leak test on the intercooler and pipes to see for leaks to test for any rich conditions, but as I said, that would most likely leave a black smoke trail. Invest in an AFR gauge with logging capabilities though, it will serve you well in future insurance for mods you do the car. Recheck the compression on a warm motor yourself an verify the compression results you posted above. If they are still that variant, find someone (or do it yourself) to perform a leakdown test to see how quickly the cylinder is losing pressure. My guess would be the head gasket is on its way out, but with only ~28,000 on the clock that is awfully soon to be seeing those sort of engine issues.

Let us know how it all works out. I subscribed and will chime in on any future posts. Good luck

 

Well Junior is a very smart tuner, so I have no doubt he made a pretty rock solid tune for your car. Don't go grilling him lol!!

as buchnerj said, color of the smoke is a pretty good indicator of what is going on. Sometimes it's just hard to tell exactly what color the smoke is when you are checking it in your rear views. Usually the more reliable source for color info is someone driving behind you.

Definitely re-do that compression test.

 

Don't take me the wrong way. I won't be questioning Juniors ability or work, I would be trying to learn from him.

The coolant was changed at the end of March, and there is no discoloration whatsoever.

I will probably be buying myself a compression and leakdown tester in the next few days, and I will do some more investigation when they show up. I will probably make myself a boost leak tester for giggles too.

One question on compression tests: Would one explanation for the relatively low compression numbers (I see 150+ per cylinder elsewhere on these forums) the fact that the test was run with a cold engine? Should the compression test be run when the engine has been run up to temperature?

I will definitely be posting more information if/when I learn more.

Thanks for all the feedback,

-Bryan

 

Yes, cold motors will greatly effect compression test results. Think about it in terms of simple science, heat expands cold contracts. You want the motor to be warm so the rings are fully expanded and as flush as possible with the cylinder walls. A cold motor will always read low, and sometimes different cylinders can have a drastic difference in compression between their cold and hot cycles. These are the rules I like to follow when doing compression tests on my motors:

1: Make sure the car is at a warm operating temperature. I usually drive mine around for at least 5 mins prior to testing.
2: Make sure your battery is fully charged. You are relying on the cranking amps of the battery to turn the motor over at normal cranking speed to show compression in the cylinders. If the charge is low the force will not be as great, and can skew the results on the low side.
3: Double checking is your friend. Go across the board and go back and verify each cylinder after the first series of tests has been run. You have to be confident in your results because compression test results are usually used as significant evidence to justify major engine work (i.e. powertrain repairs).
4: Abide by the 14-15psi rule. Any variance in compression by more than 14-15psi means there is an issue, it just might have not turned into a serious problem yet. Give it too long and it will.
5: If you have a large variance in compression and want to narrow it down to the rings or valves, use the oil trick. To rule out a headgasket problem, do a leakdown test.

Good luck

 

Thanks for the feedback everybody. I haven't had any more smoking issues since the first time there. I still mean to buy my own compression tester soon.

I did have an incident this past weekend where I blew the dipstick out of the car while AutoXing (twice). The car was fine all morning, and the first run after lunch i blew the dipstick out and coated the engine in oil. I cleaned it up figuring it was a fluke and on my second run I blew it again. I decided to give up for the day at that point.

I replaced the PCV check valve and it was sticking a bit, but I was able to blow it open with my mouth using considerably more force than the new unit (negligible force required to open the valve). Also it appeared that the valve cover vent tube was kinked.

Might the PCV check valve been the cause of the crank case pressure buildup or do you suspect I have more serious blowby issues to create that kind of pressure regardless of what the check valve is doing?

Thanks guys.

-Bryan

 

If the old PCV valve was very stiff then it is likely the culprit to cause the buildup in pressure. Replace the valve and a good way to keep pressure down is to add an oil catch on the side vent that re-routes back into the intake. Put a can that vents to atmosphere to eliminate any buildup in pressure in the valve cover, etc. You can run a catch from the back too if you are running into this problem over and over, you will also collect a lot more oil that way. Another handy little piece is this guy.

 

I intend to throw a catch can or two in once I have this problem nipped (all my PCV research has certainly led me to invest in some). I want to make sure I have the cause of the crank pressure fixed prior to adding stuff though.

I did already buy one of "those guys" yesterday, and I will probably run it for giggles anyways, I just don't want to use it to mask issues with pressure building up. Currently I am running some zip ties through the loop on the dipstick. I have them set loose enough for the dipstick to pop out past the first o-seal, but not the second one. I figure this will let me see if I am building enough pressure for it to blow again, without actually coating the engine in oil (or at least not as much).

-Bryan

 

IMO...

Thinking you're issue is crank pressure build up... one way to check is disconnect your Perrin Intake, is there any oil in there? If yes, definitely could be the issue.

A oil catch can is a good idea. But, if you go this route look into getting a catch can with an oil breather filter. Also, running larger hoses and using AN-6 fittings or larger would be recommended. Take a look at the "Engine Bay (Show & Shine)" thread... lot's of nice oil catch can setups there.

Also, the KigglyRacing HLA Pressure Regulator might be something you should look into.

Blow by (caused by crank pressure) will do two things...

1) Cause your dipstick to pop out
2) Oil into your intake through the small hose that connects to your intake pipe from nipple on your valve cover.

The white smoke will usually comes from the oil in the intake being sucked into the turbo... usually see the smoke from the BOV? and exhaust when you release(shift) the boost pressure.

Blow by usually occurs when you shift a high boost/under high load (possibly when you were driving up hill in 6th???).