My wives evo is spiking at 24/25 and settling down at 20/21 ?

she has injen i/c piping and intake, hks downpipe on a 3" exhaust w/o resonator. we did gauges too.

are these numbers normal? I would not think they are? I know I need to have it tuned and plan to have that done in a month or two but more curious.

thanks

 

Alot of people have been seeing high boost recently. Have you been boosting in 4th or 5th gear on very cold days?

 

it was a pretty cold day actually. they were 3/4 gear pulls

 

Yea the temp could be part of the problem. Do you have a mbc on it? When was your last boost leak test. It is also possible the boost you are running is 25psi but since you have a leak bleeding off about 4psi you see 21. On initial spike of boost you could see that high number for a second then it starts to leak out.

 

Op its all good no worries.you were tuned for around 23# right?

 

i'm having almost this exact same problem. i recently had my head off and reinstalled with new gaskets. my car was and has been tuned for about 20psi. my mechanic said that no adjustments were made to either my manual boost controller or my bypass valve (synapse). while driving it home from the shop, it was spiking at 30psi, and tapered down to around 25psi. no CEL came on though. since then (over the weekend) i've significantly adjusted the MBC almost all the way down, but it's still spiking at 25psi, then tapers off and holds at 20psi under full boost. anyone know what may be causing this??

 

Sometimes aftermarket BOVs and manual boost controllers can do that, does your wife have either installed? Also like everyone else was saying it might have to do with how the car is runnning due to the weather.