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#1 2017-03-21 00:26:04

DangerZone
Member
From: Colorado Springs, CO
Registered: 2015-10-11
User Number: 33712
Posts: 12

turbo surge and misfire 2 days after pro tune

So I have been saving up for an all in one throw it all together upgrades and a pro tune for a while, through conversation with a couple other shops in the Colorado Springs area I decided to go with Revolutions Performance, local, close, and seemed knowledgeable and helpful picking the right components for my goals (quick spool, hold a decent boost curve through the RPM's). Through the shop and craigslist I sourced some used components (all in great shape), did all the bolt on work myself to save some money and then limp moded the car to the shop to get the tune.

I installed:

SPT intake (used) - CL
Perrin inlet pipe (used) - CL
VF 39 turbo (used 65K miles) - Revolutions Performance
STi intercooler (used 65K miles) - Revolutions Performance
Grimmspeed ECBS (New)
Perrin DP (used) - Revolutions Performance
invidia UP (new)
COBB V3 AP (new)

The shop traced some vacuum leaks down, replaced a butterfly valve that threw a code, dynod the car, and sent it home with me the next day. Immediately I was noticing turbo surge after 4K RPM, but not super bad. The more I drove the car (moderately even) the turbo surge seemed to be so violent that I was feeling the effects in my transmission and exhaust, and eventually started misfiring cylinder 1. I have had it for two days (the shop is closed sunday/monday) so I haven't spoken to them yet, but what the hell are all those fun parts for if I can't put my foot down in 4th on the highway and get over 4K accelerating?

I am assuming this is not normal performance for a vf 39, and I also expected the EBCS and blow off to purge boost a little less violently after hitting peak boost (appears to be 15.14# at 4300 RPM)

I read a thread about misfiring being fixed by cleaning the MAF sensor, and also by grounding the block better.

Any thoughts on the misfire and the boost surging, please, let me hear your opinions. I am going to see Harvey at The Boost Creep in Denver tomorrow for a second opinion.


Silver 05 Aero- SPT intake, Perrin inlet pipe, VF 39 turbo, STi intercooler, Grimmspeed ECBS, Perrin DP, Invidia UP, COBB V3 AP
      Previous Project: -92' Galant VR4 #12/1000 ("Evo 0"): 16G, cams, gaskets and studs, tubed out w/plexi glass

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#2 2017-03-21 02:23:08

Rodman
Member
From: Long Island
Registered: 2006-03-01
User Number: 1046
Posts: 2048

Re: turbo surge and misfire 2 days after pro tune

Could be a bad coil pack or so many other possibilities, I'd bring it back where work was done and give them a chance before you go to another shop. You really don't want to floor the gas pedal till you get up to around 3,500 rpm.


2005 satin gray metalic aero, sold.
2005 black aero, rescue project, jdm STi ver 7 drivetrain.
2008 Subaru Outback 2.5i 5 speed manual daily driver.
2006 WRX, smoked, should've never betrayed 2.0L love.

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#3 2017-03-21 06:44:19

snowphun
Member
From: Central CT
Registered: 2005-11-09
User Number: 890
Posts: 250

Re: turbo surge and misfire 2 days after pro tune

Definitely go back to the shop and give them a few chances to sort it out. I hope it was a good deal on the relatively high mileage turbo, that's a part I would buy new or only from a trusted source. 15# peak boot is low as well, what was your target? Did they provide results from the dyno?

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#4 2017-03-21 23:13:34

DangerZone
Member
From: Colorado Springs, CO
Registered: 2015-10-11
User Number: 33712
Posts: 12

Re: turbo surge and misfire 2 days after pro tune

I was cautious about the turbo as well, I went through it with the shop and checked for shaft play/impeller wear and it was bomber, 0 play, 0 wear, and the hot and cold sides were in great shape, hardly any wear/weathering from heat.
I was shooting for 325 + BHP, ended up making 300 (the dyno was 250 uncorrected, the shop said to add 20% for the area). I spoke with the shop today and they said to bring it in first chance I get without an appointment and they will address it right away. I'm at 144,XXX miles, so I am ok making 15#-17# to extend the life a bit. But I feel like a boost curve that lasts longer than 4k is a given for these things, so something has to happen to extend my gear range.

The real question is, how violent are people finding boost surge with stage 2 STi's (stock VF 39). Becuase at this moment, the boost surge is so rough that it makes me back off the throttle in fear of damaging my drive train (were talking 1/2 throttle or less getting on the highway).

Last edited by DangerZone (2017-03-21 23:15:51)


Silver 05 Aero- SPT intake, Perrin inlet pipe, VF 39 turbo, STi intercooler, Grimmspeed ECBS, Perrin DP, Invidia UP, COBB V3 AP
      Previous Project: -92' Galant VR4 #12/1000 ("Evo 0"): 16G, cams, gaskets and studs, tubed out w/plexi glass

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