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Discussion Starter #1 (Edited)
When the engine warms up at idle the exhaust cam is going to -26 degrees and causing it to loose vacumn and stall. I can unplug the solenoid and per evoscan it will sit around minus 6-8 degrees and stay there. with it plugged in after warming up it will drop to around 26. i just had the engine apart and Know the cams did not have this problem a few months ago. I swapped the solenoid with no change and going to try the cam sensor to night just because i have one. I was wondering if any one else has had a similar problem and if so how did they fix it? I am curious if there is anyway to clean the cam gear passages with out pulling the cams incase maybe some debris got in it. There was no filter for the mivec control which the screen is now readded to it but it did not start the problem till recently.
 

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Discussion Starter #2
I just swapped out the cam sensor and no change. Whle driving the cams match where the should be or close but idle it goes screwy.
 

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Discussion Starter #4 (Edited)
10psi at idle and 55-60 at 3500. does anyone know the value it shows in evoscan for exhaust cam timing when the acuator is unplugged? so far swapped out cam sensor, solenoid and cam gear, checked cam bearings, reflashed to a older rom i had. unplugged it reads about 3.25 degrees actual. plugged in in evoscan shows up to -22. to make it more confusing the mitsubishi mut3 shows the cam is going advance and not retarding but just sticking with evoscan data.
 

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10psi at idle and 55-60 at 3500. does anyone know the value it shows in evoscan for exhaust cam timing when the acuator is unplugged? so far swapped out cam sensor, solenoid and cam gear, checked cam bearings, reflashed to a older rom i had. unplugged it reads about 3.25 degrees actual. plugged in in evoscan shows up to -22. to make it more confusing the mitsubishi mut3 shows the cam is going advance and not retarding but just sticking with evoscan data.
0 degree actual .. mut3 is correct..

mivec is disabled below 1133rpms and 77degreesC (I think)
 

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But by "disabled" ... it's actually running full advance at idle (0 degrees)
wth low/no oil pressure it will run full retard

is that correct boffins??
 

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Discussion Starter #8
Just as a update I never did really figure this problem out but it seems to be working now. I pulled the head and found no problems, pulled the pan and checked oil pump clearances, swapped out cam gears which helped a little, blew out oil passages, repulled the pan and checked rod clearances, replaced the oil pressure relief valve, swapped cam sensors and solenoids. I found out the oil pressure gauge i had used was messed up so i installed one to leave in the car now. 20-22 psi idle. Either it had something lodged somewhere or it was heat from the downpipe causing the exhaust cam to go funky.
On the bright side i pmd a person who had a mivec problem caused by a dirty screen and he just pulled the plug in the head and used compressed air to blow it out.
 

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how much oil pressure are you supposed to have at idle?

Oem specs says abouve 4.5psi but how much above 4.5psi is good?

At 10psi were you having problems?
 

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how much oil pressure are you supposed to have at idle?

Oem specs says abouve 4.5psi but how much above 4.5psi is good?

At 10psi were you having problems?
The 4.5 is for the stock clearances and cams etc. I have been working with A LOT of people having similar issues and the data seems to be piling up. I hope to be posting a bit of an email tonight to put some light on this.
 

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The 4.5 is for the stock clearances and cams etc. I have been working with A LOT of people having similar issues and the data seems to be piling up. I hope to be posting a bit of an email tonight to put some light on this.
I can not wait to read up on this !

What type of oil pressure should you have on a rebuilt engine at idle once the engine is warm ?

I met someone with an Evo 9 and he has a rebuilt engine, oil pressure at cold start was about 80 psi and when it warmed up it went down to 40 psi.

Thanks !
 

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Discussion Starter #15
yes that was confusing me at 1st then i relized that my full advanced was others full retard so i have to remeber to stick with ecuflash/ cobb/ evoscan data values and not actual.
 

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I just posted a thread on this, monitor both and see where your cam timing goes when oil pressure drops.
just make sure we're singing on the same sheet of music

Intake = max retard at start
Exhaust = max advance at start

not affected by oil pressure since its mechanical stop ..
 

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Discussion Starter #17
I never did post what all ifound that caused this. 1st the gauge i was using was wrong it had been hooked to a auto trans at work so read wrong and to low. i installed a gauge now and 21 psi at 900 rpms. 1 problem was i had a exhuast leak at the downpipe to the turbo which was small but caused extra heat on the exhuast cam solenoid making it act funny. after fixing the leak it made it better but not all fixed but i did verify the problem by putting a temp head shield there and it worked. so after fixing that. I did the stuff above like checking clearances and passages but no luck and the problem went away. I forgot that I had raised the idle to 935 to solve it. The main problem apears to be the valve springs 85 supertech dual valve springs are just alot stiffer from the factory causing issues. So raising the idle a little was enough to stabilze it.
 

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just make sure we're singing on the same sheet of music

Intake = max retard at start
Exhaust = max advance at start

not affected by oil pressure since its mechanical stop ..
This is only partially correct. The cams are designed to default to 0 on both cams in a resting state. However, they rely on oil pressure to do so. The EX cam has a helper spring to keep the cam in a neutral, or 0 deg state at idle. WHen you have a heavier spring, larger cams and lower oil pressure at idle, the Ex Cam can not stay in the '0' position and falls to -30deg.

John
 

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This is only partially correct. The cams are designed to default to 0 on both cams in a resting state. However, they rely on oil pressure to do so. The EX cam has a helper spring to keep the cam in a neutral, or 0 deg state at idle. WHen you have a heavier spring, larger cams and lower oil pressure at idle, the Ex Cam can not stay in the '0' position and falls to -30deg.

John
:yeahthat: Exactly! What is supposed to be only applies to a stock engine.
At idle the car is fighting to get back to zero do to the stiffer internals. The dinky spring and minimal oil pressure just can't make that happen.
 

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Just had a set of Cosworth MX-1 cams installed and while the car idles like a champ after a few tweaks, as soon as the MIVEC kicks in above idle the exhaust cam wants to retard an extra -15 if I rev to 2k rpms. At idle both the intake and exhaust cams match target to actual so it appears something MIVEC related is wrong.

I'm going to go out and test if the exhaust cam has issues while under 5 / 10 /15 psi boost or if it's only cruise and off boost. Hopefully something simple but since I haven't researched it heavily yet I'm going to continue my search for an answer.
 
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