changed the spark plugs with new oem ngk . now it misfires and idles rough. code p0300 pops up. .also can some one tell me where i can get a vacuum line diagram for evo 9

 

Hey buddy-

Check your gap on the plugs and then check this thread out https://www.evolutionm.net/forums/ec...0300-test.html

I just disabled the code on my car - and it runs noticeably smoother


-Bink

 

the hose coming from the top of the motor where it says mivec it disconnected is this a vacumm line?

 

Can you take a picture of the line your talking about ?



-Bink

 

My Evo 8 has a vacuum hose diagram affixed to the underside of the hood.

 

As stated check your plug gap, I had the same problem. Ended up switching plugs entirely and bumping the gap down from .024-.022. Ran fine after that.

 

well i gapped them to 23 and the service light did not come back on. IT now has a good idel . not a perfect idel . as you can tell this is my first evo. do evos have a minor unstable idel. i had a subaru before and it had a stable idel ,couldn't tell if the car was on some times. i still have the problem with the evo turbo. got the car to spool the turbo but it looses boost once i pass 3000 rpms.

 

do a boost leak test

 

My idle has only been unstable since I added the Cosworth cams about 1.5years ago. I had my car tuned recently and my tuner cleaned it up pretty good, not to sure what he did. It's still a PITA at lower RPM's sometimes but I just got used to it. As for losing bost past 3k do a boost leak test like the guy above said.

 

how can you tell if the turbo is fried. I had the car to full wot on first gear and hit 7,000 rpm i did this in every gear until i hit fifth . could this do damage to the turbo. Ever since then i can get the turbo to spool like it had that day. I could hear the turbo whine loud when i bought the car . Now when i try to hit full wot . i can not . It feels like the turbo falls short and looses boost. am going to do the boost leak tests next week . i have never done one . Is the any one in the reading p.a area that has done one before ?

 

it is coming from the top of the motor head . is this a vacuum line . it was disconnected .where do i reconnect it and where can i get a vacuum line diagram

 

that is supposed to be connected to your air intake tube. after the MAS and before the turbo. if you have an after market air intake, you may not have it. it's a breather for the valvetrain. you can either put a filter off the valve cover (to keep dirt from getting in) or find a way to route it back into the intake system. preferably the latter.

**edit. it looks as if you have the OEM intake/air box. so, look for a nipple sticking out of the intake tube, under the diverter valve. you will see where it should attach.

 

i reconnected to the diverter . I was hoping this was the reason my turbo was not working properly but its still acting the same .

 

Here is the vacuum line diagrams:

1) http://bayimg.com/GAeHDaAca

2) http://bayimg.com/GaehEaACA


I would go through and make sure all the vacuum lines are hooked up in the correct spot and also do a boost leak test - then we can go from there



-Bink

 

thanks.

well since i changed the plugs on Friday . The car was running good except for the turbo problem am still having. No check engine light until this past monday on my way to work. As soon as am going up a steep hill and step on the accelerator the service light came back on. I checked the code again and now i have the po300 and a po172 . I will hopefully be doing a boost leak test next monday.