I've had my car for three weeks now, and last week I installed a defi boost gauge. (didn't have one) The car was hitting 20psi in all gears and sometimes 21psi. Then last night the gauge started acting funny and I noticed it wasn't pulling as hard. So today I fixed the boost gauge the vacuum line had a kink in it in the gauge pod. Now, the car only hits 17.5 to 18psi in 1st and 2nd, around 19psi in 3rd, and 20psi in 4th and 5th. The only mod I have is the Greddy type-s blow off valve, but I don't think this is a problem it's been on there since the 2nd day I got the car and all of the connections are sound, and I used teflon tape on the upper valve. I suspected that it may have had a ECU reflash because a couple of friends that rode in it said that it pulled harder than a stock Evo. But the guy at the dealership didn't say anything about it when I asked him about mods, but I heard one of the other salesman say something about having a little work done under the hood, but everything is stock, so that's what led me to believe that it might have had a ECU reflash. Thanks for any help.

 

some evo's can boost higher than others, for example my can hit 24 to 25 psi where my friends hit 20 or 21 and hits fuel cut. some can just pull more boost.

 

but why would it just stop doing it?

 

A little more info....I drove the car today and I'm getting a spike and then it's loosing boost pretty bad when I hit approx. 5500 rpm. (1st, 2nd, and 3rd) Do I have a leak?

 

did you check to make sure the gauge is on properly

 

Yeah the gauge is good, I've double checked it. The car just don't feel right.