EVO 8 inconsistent boost drop
 

Hello All,

My 03 EVO has recently been doing something really strange. I daily drive the car, most of the time it boosts perfectly, however other times it suddenly drops boost. Sometimes I do two back to back pulls when on one pull it boosts properly and the next pull it drops.

The boost peaks at 1.6 bar as I floor it for 1-2 seconds and then suddenly drops at around 0.9 - 1 bar for the rest of the pull.

Could a boost leak cause such a problem or could it be an electrical problem as its inconsistent?

The car has the following mods:
HKS exhaust system and downpipe
HKS suction and induction
Turbo Smart Dual Port BOV
Turbo Smart EBOOST controller
Evo 9 turbo
Walbro fuel pump
Custom Reflash
bigger intercooler and ralliart piping

Hey welcome & thanks for posting. Yes, for sure, do a boost leak test. On an 03, especially one that see's daily driven miles, a boost leak test is in order

:beer:

Do a boost leak test, and thoroughly inspect the BOV and boost reference line that goes to the BOV.