I noticed a sluggish boost today in both normal and sport mode. If I lay into it the car seems hesitant from 3,500- 6k. once it hits 6k it slams you into the seat....Pressure reads fine on my end. (1 bar in normal and 1.2 bar in sport).

I have a EVO 580 kit with EVOMS Diverter valves.... Do you think one of my valves could be sticking? Anyone else experience anything similar so l know where to start?

A few months back I had a repair made to the passenger turbo, the actuator for the VGT had fallen off and needed to be replaced.. in that scenario the boost would kick in but was very jumpy, almost as if the car was trying to leap forward but kept getting pulled back because the valve was not holding open. This feels a bit different than that issue.

Thanks in Advance.

 

Does boost pressure build and maintain steady while the car is hesitant and down on power? If so, that is commonly a sign of an ignition or fueling issue--worn spark plugs or coils, bad fuel, or an air leak or bad sensor. Is the CEL on and is the car throwing any codes?

 

are you running the stock clutch?

 

Hi flow cats? if so how many miles on them?

 

list all your mods....helps a lot.

 

What gear was the pull? 6k RPM Boost sounds like a 5-6th gear pull.

 

yes, the initial boost is fine then it seems to level off rather than continuing to pull hard. If I stay on the gas when I hit 6k it will slam your head into the seat with a large input of boost.

Best way to describe it would be like you are towing a boat from 4k-6k... then the boat falls off the hitch at 6k. Dont ask me how I know what this feels like

Hi flow cats? if so how many miles on them?
Yes, 200 Cell Cats. Not sure when these were installed, I purchased this car used with the modifications already installed. The dealer that I purchased from still has great communication from the guy that traded the car in, he has been helpful in the past. I may have to reach out again to collect the dates on these installed items.

list all your mods....helps a lot.
EVOMS Stage 2 Tune
EVT580, upgraded plugs and forge diverter valves... I think this is part of the EVT 580 package
Techart Exhaust w/ 200 cell cats
Plenum appears stock, there has been no mention of an upgraded clutch (Service records show a new clutch at 30k... I have 43k now)

It was really hot today so that may be impacting the performance but It was noticeable on my way to the office this am. Ill check it again this weekend. Ill take a look at the actuators and make sure they more freely, then burn through this tank of gas and try an additive on the next fill up to see if that helps. Im a good hour away from the nearest dealer so Id like to run through all the simple fixes on my end first before I head to a dealer.

 

I tried 2nd and 3rd gear pulls to 6k.... both felt about the same.

 

There are a lot of possibilities. I just yesterday had a clutch replacement as my car provided A slight slip occasionally on the hwy under load and full boost. Then some 5 "drives" later it was acting strange in 2-3rd pulls, like once boost spooled it would half slip/grab and lurch forward in high rpm. I never had the heart to stay WOT through the process and decided the clutch may be on the verge of really slipping but not quite and started grabbing once things heated up the fw surface. While I am obviously in the break in stage, I'm being very nice to the clutch but had to dabble slightly into some roll on power to see if that was eliminated and seems to be the fix so far. Your "feeling" sounds similar to what I describe.... You mentioned the clutch was replaced at 30k, but to what? Was the EVO580 kit already installed when you bought it? Was the car still stock at 30k when the clutch was replaced?