Spiking 24, dropping to 10-11 ...
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Spiking 24, dropping to 10-11 ...
Def a leak right....? got a gauge hooked up today to see what was actually going on, at first it was spiking way above 25+ so i turned it down on the mbc. Seems to be spiking at 24 and dropping immediately to 10-11 mid rpm range. I've checked all vacuum lines and tightened all clamps. Think its throttle body seal guys?
Doesn't sound like a boost leak, sounds like a wastegate or boost controller issue. What does it do when u run it straight off wastegate pressure? Have u tested it for boost leaks?
Last edited by gpfury86; Apr 8, 2012 at 06:25 PM.
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Going to make myself one somehow tomorrow to test for leaks, I Haven't tried to run it off wastegate pressure I was assuming thats why it was dropping to 11psi and running off the wastegate could the MBC Be bad I hear air coming out of the tiny hole but my last one did that also. I made sure the line all go where they are suppose to aswell, I double checked first thing when I got back home with the car.
Its a 05 has 96K on it all stock nothings every been changed under the hood so far. I just put a new DV on it the plastic one was leaking I thought.
Its a 05 has 96K on it all stock nothings every been changed under the hood so far. I just put a new DV on it the plastic one was leaking I thought.
Last edited by kaonashi; Apr 8, 2012 at 07:29 PM.
You mention having changed the diverter valve. Did you install a new factory metal IX DV in place of the original plastic POS. Did you install the MBC yourself? Did you buy the car used?
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When you say that it is all stock and nothing has been changed under the hood you are not being completely accurate. Does it still have a catalytic convertor on it? If so, is it the original cat with over 90K on it? Do you have the original, factory O2 housing and stock down pipe still on it?
You mention having changed the diverter valve. Did you install a new factory metal IX DV in place of the original plastic POS. Did you install the MBC yourself? Did you buy the car used?
You mention having changed the diverter valve. Did you install a new factory metal IX DV in place of the original plastic POS. Did you install the MBC yourself? Did you buy the car used?
The car was purchased 2 weeks ago from a Evom Owner. He told me it had a boost leak from stock plastic DV. He disconnected the boost gauge before I got to look at the car because he was assuming the gauge was leaking. I turned the mbc all the way down before i drove it home for the reason of not knowing what it was boosting off the controller until yesterday when I re hooked up the lines.
The MBC & Gauges where the only thing on the car. Stock Intake, Stock o2 housing, Stock DP, stock cat,& stock I/C Setup, previous owner installed Buschur Catback.
It has a IX DV now.
I did not install the Hallman, but I un hooked it and re attached it as to the way I had my last MBC Installed which was pretty much exactly the way it was already on the car.
Wastegate to side without Hole , and Straight out to the vacuum on the valve cover not the "Breather for Intake".and has the tiny hole on the fitting.
Last edited by kaonashi; Apr 9, 2012 at 08:16 AM.
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Found a rats nest of unhooked line by the stock boost control solenoid. Uploading pictures. the breather underneath the intake and the slave cylinder have screws in them capped off????
Last edited by kaonashi; Apr 9, 2012 at 08:56 AM.
Ok guys this is crazy stuff let me explain a bit more.
The car was purchased 2 weeks ago from a Evom Owner. He told me it had a boost leak from stock plastic DV. He disconnected the boost gauge before I got to look at the car because he was assuming the gauge was leaking. I turned the mbc all the way down before i drove it home for the reason of not knowing what it was boosting off the controller until yesterday when I re hooked up the lines.
The MBC & Gauges where the only thing on the car. Stock Intake, Stock o2 housing, Stock DP, stock cat,& stock I/C Setup, previous owner installed Buschur Catback.
It has a IX DV now.
I did not install the Hallman, but I un hooked it and re attached it as to the way I had my last MBC Installed which was pretty much exactly the way it was already on the car.
Wastegate to side without Hole , and Straight out to the vacuum on the valve cover not the "Breather for Intake".and has the tiny hole on the fitting.
The car was purchased 2 weeks ago from a Evom Owner. He told me it had a boost leak from stock plastic DV. He disconnected the boost gauge before I got to look at the car because he was assuming the gauge was leaking. I turned the mbc all the way down before i drove it home for the reason of not knowing what it was boosting off the controller until yesterday when I re hooked up the lines.
The MBC & Gauges where the only thing on the car. Stock Intake, Stock o2 housing, Stock DP, stock cat,& stock I/C Setup, previous owner installed Buschur Catback.
It has a IX DV now.
I did not install the Hallman, but I un hooked it and re attached it as to the way I had my last MBC Installed which was pretty much exactly the way it was already on the car.
Wastegate to side without Hole , and Straight out to the vacuum on the valve cover not the "Breather for Intake".and has the tiny hole on the fitting.
What you need to do it connect wastegate to MBC and Turbo also to other end of MBC then from the MBC you can T in your boost gauge or w/e else.
I'll have to go outside and look at my engine bay to tell you which one goes on what part of the MBC. That's the most accurate. I hold 30lbs of boost to redline on the stock turbo on e85 with my hallman and STOCK wastegate.
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Followed this : https://www.evolutionm.net/forums/ev...procedure.html
Its setup like Option #2 I'm going to check for cuts in the lines I guess.
Yeah my last 03 Evo held 24 and never tapered thats why im just assuming its some massive leak. Found a crap load of vacuum lines just zip tied and not connected. loading pics

Stock BCS is capped off, the lower intake line is just open to pull in air at will, Stock BCS capped.

The Vacuum line on top of the slave is capped off?

The old stock lines with the pills in them was just zip tied in place not hooked up to anything.
Everything is capped off as far as I can tell, when I turned the MBC down it sounded like sand was in it kind of like a gritty noise. maybe the seals broken in the mbc.
Its setup like Option #2 I'm going to check for cuts in the lines I guess.
Yeah my last 03 Evo held 24 and never tapered thats why im just assuming its some massive leak. Found a crap load of vacuum lines just zip tied and not connected. loading pics

Stock BCS is capped off, the lower intake line is just open to pull in air at will, Stock BCS capped.

The Vacuum line on top of the slave is capped off?

The old stock lines with the pills in them was just zip tied in place not hooked up to anything.
Everything is capped off as far as I can tell, when I turned the MBC down it sounded like sand was in it kind of like a gritty noise. maybe the seals broken in the mbc.
Last edited by kaonashi; Apr 9, 2012 at 09:45 AM.
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wastegate doing spike goes to 11 and stays.... thinking the MBC is broken or or defective? The previous owner said he thought he had it hooked up wrong but I checked and its correct, unless the fittings are on the wrong sides.
What you need to do it connect wastegate to MBC and Turbo also to other end of MBC then from the MBC you can T in your boost gauge or w/e else.
I'll have to go outside and look at my engine bay to tell you which one goes on what part of the MBC. That's the most accurate. I hold 30lbs of boost to redline on the stock turbo on e85 with my hallman and STOCK wastegate.
I'll have to go outside and look at my engine bay to tell you which one goes on what part of the MBC. That's the most accurate. I hold 30lbs of boost to redline on the stock turbo on e85 with my hallman and STOCK wastegate.
Last edited by gpfury86; Apr 9, 2012 at 12:50 PM.
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Fixed, mbc was assembled wrong the hole nosel tip was suppose to go to waste gate side & it was on the intake side of mbc. Spiking 24 tapering to 21 @ redline. So moral is if u buy a used car double check all the work ! +1 for mbc pointer


