Hey guys! Finally traded my skyline in for a evo 8! I am absolutely in love with it although today I noticed some intermittent boost issues.

Basically the car runs smooth as silk. Perfect idle, smooth like butter. Usually on WOT the boost comes on hard and will throw you back in your seat, and I can hear a crisp turbo spool. Other times on WOT the turbo feels slightly laggy and wont give you a shove in your seat feel, It feels as if the turbo looses boost pressure or timing gets pulled or something? It will rev like an naturally aspirated car.

I have no boost gauge as the car is completely stock so I am just guessing here.

Any help would be much appreciated guys

 

Boost leak or EGR valve hoses?

 

An intermittent boost leak?


OP, I think now might be a good time to invest in a Tactrix cable and start datalogging so you can see exactly what's going on. Or alternatively take it to a tuner. If the car is indeed pulling timing then I think you have a real cause for concern.

 

First off. You can't start a thread saying you got a new evo, and not post pics! :P

Second, grats on the purchase.

Lastly, would help a bit if you told us what mods are on the car. First thing I'd do is check for boost leaks, and you also want to make sure you aren't knocking when going WOT. Was the car tuned previously?

 

Hi guys! Thanks for the replies, and I'll be posting pictures of my new evo shortly

​​the car is completely stock standard. Like it came from factory. No mods at all.

it's really strange! At times it boost nice and other times it feels like im not boosting at all even when I'm WOT. The car is not blowing any smoke and drives incredible smooth, it just has this boost issue

the car has 100k on it. Do you guys think it could be a blow off valve or wastegate leaking? Is it common thing for evos?

I'll be doing a boost leak test tomorrow.

 

In my experience boost leaks are pretty common.

 

I'd boost leak before anything else. When i bought my car, it had a ton of boost leaks i had to fix before i got it tuned.

 

Hey guys

I think I found the issue.

Leaking blow off valve :/

Do you think restricting air flow to the MAF would cause my boost issues?

 

It is possible your Evo was previously tuned with the pod filter or something similar. Ive noticed changing the size of the filter has an effect on the air/fuel ratio. Going from a smaller to larger intake filter can lean out the AFRs.

 

Yeah that sounds like it could be it! Also the issue only occurred once the car got hot. Still need to do a boost leak test though.

 

Ahhh this is so frustrating!! Problem hasn't gone away.

​​​basically, when the car has just warmed up its fine. I can get at least two WOT pulls before the issue comes back. I can park the car for 10 minutes and go for another drive and do another WOT pull and will be ok. As soon as I attempt WOT pull for a second time the car feels like it's revving like an NA non turbo car. The turbo doesn't become as audible and crisp and it suddenly becomes laggy.

its the same recurring pattern. Let the car cool down and ifs fine until I hit WOT.

I am so frustrated because I have sold my skyline due to non stop issues and stress and now I'm going through the same crap!

 

If I were you first thing I'd do would be a boost leak test you can make one yourself for less than $10 buck. Than come back and update us.

 

Boost leak test 👍🏼. Maintanance on the Evo requires commitment and fortitude.

 

Is there anything I could do to stop these clamps from leaking guys? Can I remove the blow off valve completely and block of the holes? Although I know it will dose and potentially cause damage to the turbo... Or would you guys suggest an after market metal intake pipe? These damn clamps and blow off valve are going to be the bane of my existence.

by the way you guys have been super helpful and supportive I absolutely love my evo despite the issues I am having and I am super committed to making this car A1 quality.

 

Are the poppers seated into the rad support for the intake lid snorkel? If they are missing the Snorkel will lift on acceleration and restrict airflow, car will feel like it's ran out of power completely.