EvolutionM - Mitsubishi Lancer and Lancer Evolution Community - losing power, give me a list of things to do to find my issue

- Evo Engine / Turbo / Drivetrain (https://www.evolutionm.net/forums/evo-engine-turbo-drivetrain-22/)

- - losing power, give me a list of things to do to find my issue (https://www.evolutionm.net/forums/evo-engine-turbo-drivetrain/750316-losing-power-give-me-list-things-do-find-my-issue.html)

Still, if his gauge is right, 100 psi is not a lot of compression.

No, it's not. But I have a feeling the gauge isn't right. I went through 4 kits once before I found one that worked and had good readings. Sometime it's just the Schrader valve not working right.

Quote:

Originally Posted by Jonno99 (Post 11834389)

Ok just got back from another track day, I now know I have an issue but its slight. The car is an Evo 9 with only 77k klms on the clock and I have been noticing on the road a very slight power drop which my timer on the track proved. I was down on top speed on the straights around 15 klm per hour. I was down 2 seconds a lap too. Also puffs of smoke were being seen behind the car on gear change at WOT. It also spits a little oil on start up in the mornings. The car is mostly stock. I also noticed one lap it actually lost about 20% power for half a lap then came good again which is weird and never repeated that.

ok so I understand about boost leaks and have been over the pipes and one of those boost smokers into the inlet tests and nothing was seen escaping. I want to also do a compression check, that's easy, I can buy a comp tester this weekend. I am also suspecting the journal bearing on the turbo, how do I test for that? Can I lose boost with a worn journal bearing?. Is there anything else I can check or test?

The car hasn't got that many miles on it which concerns me of what it could be.....thanks anyway

Do you have evoscan? if you do then a good thing to look for is knock sum. If there is a significant amount of knock then the ecu will pull timing and can also switch to a lower octane fuel map which will be more rich than your high octane fuel map and that will cause a noticeable amount of power loss. Then when there is no more knock the ecu will resume to running the high octane fuel/ignition maps and power will come back.

No mate, its locked with Ecutek, from the previous owner, ok so I've got to the turbo there is no in out freeplay only a slight bit of up and down, very tiny click so the journal looks ok but i did a boost test and i couldnt get the system to hold pressure at all and i found the air was leaking out of the BOV, i think its the original black plastic one, is this a common issue of boost leaks through the BOV?

Yes, the plastic BOV sucks. Get the metal one from an Evo9.

Quote:

Originally Posted by letsgetthisdone (Post 11835507)

Yes, the plastic BOV sucks. Get the metal one from an Evo9.

with your experience should i go for one of the funky after market adjustable bovs or the alloy evo 9 ones?

The 9 BOV works the best for the stock turbo.

Quote:

Originally Posted by letsgetthisdone (Post 11835572)

The 9 BOV works the best for the stock turbo.

I've been doing a boost check with compressor right on the turbo, I found a little hole in the little hose that goes to the top of the BOV, I also found air leaking from the PCV valve, not sure if this is normal from all the searches I have done it seems the stock PCV all leak at 10 psi? some people put another valve in series or change out the PCV valve to a non standard, so I have plugged that and there's still a leak that I am looing for, will have another go at it over the weekend..... I've ordered a good catch can and a new bov

Quote:

Originally Posted by Jonno99 (Post 11836228)

I also found air leaking from the PCV valve, not sure if this is normal from all the searches I have done it seems the stock PCV all leak at 10 psi?

There's more than one PCV valve used on Evos. The valve supplied on the USDM cars don't have this problem. Aftermarket valves do.

I'm trying to find a mystery boost leak, i am boost leak testing direct into the turbo and have the hot side plugged, air seems to be escaping within the turbo, is this common? I don't want to pull the turbo and have to do all the gaskets

Try this...disconnect the charge pipe at the throttle body and plug it. Plug the line going to the valve cover from the turbo intake hose.Clamp the tubing to the BOV shut as well as the boost line to the turbo. Then pressurize the system using your pressutre testor adaptor. This isolates the turbo and IC system. Listen for leaks..Trace with soapy water. Fix any leak you find.

I used an inline ball valve with a air gauge tapped in to add pressure slowly then top out at 30 psi. If you have no leaks and the turbo is tight then the pressure wont drop at all. Make sure you have the adapter on tight....if it comes off ...it can be deadly missile !!!!!!!!! that is why I add pressure slowly

This isolation technique also means you don't have any open valves in the engine etc so no constant loss.

I used to take the TB off and block both sides with one side with the air compressor adaptor on it and all ports blocked then pressurize it. This isolates the TB seals . any leaks show up instantly.

BTW go ahead and get the OEM PCV valve. I make the dealer take it out of the package and i blow hard into it to make sure it shuts off tight BEFORE I give them money.. :-) Aftermarket ones are absolute crap I have tried about 6 different brands and they don't hold pressure at all.

Lastly...replace ALL the factory clamps with high quality T-bolt clamps.

Regards,

Milburn