Hi everyone I just bought a 08 evo x with 28k miles this past weekend and today I got concerned. Give me a few minutes of your time to explain.
Specs :
- Artisan downpipe back catless single exhaust
- Intake cone filter with stock piping
- AEM fuel/air gauge with a serial port installed in the driver side where the fuse door is. The gauge isnt working at the moment just shows random p01 p02 codes i guess.
- a AMS performance sticker on the dashboard for an extra 15hp
- Everything else seems stock.

The car has a Defi link boost gauge set up but wasn't working because the last owner ran the wire across the firewall from the driver side to the passenger side to feed it through the firewall. Needless to say the exhaust heat burnt it up.
So today I cut the burnt part and rewired it, ran it through the driver side and got the boost gauge to work. Now what scares me is that the boost gauge was a 25lb + 3 more sticks so I'm assuming a 28lb gauge.
When I stomped on the car to check if it was tuned the needle was bouncing off the other side of the gauge indicating the car is boosting over 30lb and settles down around 26lb! Yikes.
I got the car like that with no information what so ever besides the obvious down pipe-back exhaust (no cat) a intake cone filter the boost gauge a non working aem air/fuel gauge and rims. I also noticed the exhaust manifold heat shield was missing as well. sigh..
I'm hoping its just a faulty boost gauge. I'm waiting for ssp shop here in Houston to be dis-occupied so I can take it and get it diagnosed to see whats going on but I'm anxious and if any of you have any information that could potentially prevent a catastrophe I would greatly appreciate it. Thank you very much.

 

1.) Lower your boost if it has a mbc, try to lower it al the way. 2.) You can try to get a mbc if you dont have one and that will lower it.
3.) Do not run that high on those aftermarket parts you will blow you head gasket.
4.) Take it to a shop let them fix it.

 

Get a proper tune.

 

Yea it needs to be tuned correctly. Just drive it very slow around town just to be safe. Don't "stomp on it" like you said and you should be fine until you get a tune.

 

thanks for your input guys i already contacted ssp in houston for a tune date. i also ordered a mbc and a aem f/a set up.

 

Iam pretty sure it is not the tune, but it is allways good to check. I think the mbc will solve your problem.

 

thanks. Well either way the car doesn't really seem to be running smooth so it may be a tuning issue. I checked the Waste gate for any vacuum hose leaks i didn't try to check the rod to see if the previous owner fooled around with it though. i think ill leave that for the tuners to figure out.
30k mile service + tune/diagnose = happy car and sad and skinny wallet

 

I think u should get retune.

 

Sounds like you have a 3-port on the stock tune.

 

I just checked. No 3 port no mbc no disconnected vacuum lines, im guessing a bad tune.

 

it has the stock mitsubishi dual boost control solenoid setup?
wonder if it has the stock boost pill.

either way, i would buy a 3 port and get it tuned and that will fix it up and you know it's safe.

 

you could lower the boost error correction table so it cant add boost, only drop it.. and then lower the wgdc tables for a temp fix.. of course it would require reflashing the ecu though and having a programmer.

if you have the cable & laptop i could help you for free until you take it somewhere.. or do whatever you're gonna do with it..

as others said, may as well just get a full tune though and get it checked over in person by a reputable shop. i would suspect it has something faulty with the wastegate.

but just thought id throw that out there.. i dont mind helping people on little quick fixes for free.

 

thank you for your input. I have set up a appointment over at ssp in houston for next friday.

 

Without datalogging it you never know how accurate the boost gauge is either, so while it might read 30 psi on the gauge, I've often seen them read 1-2 psi high especially if they also read vacuum. SSP Texas should get you going in the right direction, just take it easy on the throttle until you get it checked out and corrected.

 

thought it was illegal for dealerships to sell cars without a cat? private party?