Hello all, Evo X n00b here... I did my fair share of reading the last few days, and I still don't quite understand what can be causing the issue.


This past weekend I picked up a 2008 GSR, for mods it has an Injen intake, UICP, an aftermarket BOV (which is recirculated) and an AMS Widemouth downpipe (but stock cat & catback). It has the stock boost control solenoid, and it has a Cobb tuner which I am not a fan of, currently running a Stage 1 tune flashed for 91, for an intake.


I am having crazy overboost issues. In any gear 1-4 (haven't tried 5th, but there's no point) at any RPM if I go WOT it will shoot up to the moon and boost cut. Now, sometimes, if I ease into it partial throttle and build up to about 20ish PSI or whenever the WGA is supposed to open up, and then go full throttle it will hold that boost level and not go over. So I know the wastegate is opening.


I have also gone over the lines and everything appears to be where it needs to be.


SO my question is, what is causing this? The stock BCS or the Cobb? And how can I fix it? I was thinking to ditch the Cobb, get a 3 port BCS and a full exhaust and have it properly tuned on say Evoscan. Is there any other way?


Thanks in advance

 

Outside temp? Get it tuned and that will take care of it.

 

six40

I had the same issues, but never really resolved them. First, contact COBB, they are great with customers and will ask for a log.

Second, did you input the correct MAF/INTAKE setting for your intake? COBB has a video on their website that shows how to change the intake part of the map, which has to be done if you are not running a stock intake.

 

Are you reading it off the COBB AP or do you have an actual boost gauge? I think a boost gauge will give you a truer reading than the AP. I have the a stage 3 tune with all the necessary parts and I'm good but if I try to go back to stage 2 it over boosted like crazy so you might be a stage 2 rather than stage 1 right now with your bolt ons. I'd try that first and see what happens.


Different topic, be careful having that widemouth DP and stock catback. I did the same thing and I actually heated the cast down pipe blue bc of the back pressure heat. It welded the studs to the turbo housing and I had to drill them out...it Fing SUCKED! So I would go ahead and finish off the exhaust asap if I were you.


Anyway good luck and I hope COBB can help but I bet your just on the wrong stage.

 

Hey guys thank you for the replies. I will update this now since the issue was resolved.


To answer some questions, I do not have a wideband but I do have an aftermarket boost gauge so that's what I was working off of. As for the exhaust, that's a solid point... I don't drive the car enough right now (sat for 2 weeks) and when I do I didn't beat on it due to the problem. I used it more like a normal econobox lancer so far LOL but the exhaust is on it's way. I have a Magnaflow CBE I just got in new, and a friend is fabricating me a 3" test pipe to connect the AMS downpipe to the catback (which is also getting the 2.5" bottleneck cut off and replaced with 3" to make it a true 3" front to back)


The problem was actually the fuel pump relay... I knew about the problem but it took me a while to put the 2 and 2 together until I looked, realized it's the black one, and switched it out for the horn relay. Now my Evo doesn't have crazy spikes (assuming it was the lean conditions and timing out of whack causing it to spike) and pulls smoothly all the way up to redline without and hesitations.


Also when I look out in my mirror I almost can't see the person behind me at WOT because now it smokes like a rich-*** 2008 X should Before it would shoot a puff, now it smokes a tonne.


So thank you all for the replies... And anybody else that comes across this thread if you may have issues with your X up top and are new to the platform... Take the minute to pop the hood, take the fuse box cover off and look over the relay. It`s a simple fix. Now that I know that is the problem, I will be getting all the relays replaced to the new revised models.


Cheers

 

you have a 2008 X? I have one of those , and i also had to change the relay.

But what the fuel relay has to do with the boost spike, just asking.

 

Exactly. Nothing to do with it? You are trippin man unless you have a custom tune which I hope you do, you shouldn't be running an ots map with your setup at all!

 

And you call this "resolved"?