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Need Help After FMIC install Boost spikes to 20 psi w. 16G

After installing Dave Brode Intercooler with 2.25 piping, my car spikes to 20 psi in at about 5-6k rpm.
I have a MBC and it was set to 15lbs with stock intercooler. After piping and FMIC it would spike to 20 psi even though the MBC is one click away from 15.

It will hit 20psi and the car detonates, or reaches fuel cut im assuming the ecu was set like that for safety.

The car now has erratic idle, from about 15-1800 rpm it would jump up and down.[im assuming BISS SCREW?]

I tried doing a boost leak test, but i heard nothing. My regulator was set to 20 PSI, but the gauge in the car was reading about 0-.5[im assuming i need to turn the air up, but afraid of letting go to high?]

My setup includes

MAFT
650 Injectors
ecu chipped
evo3 16g
2g Downpipe
greddy Type S bov [which was a PITA with car building boost if was a little to hard or soft]

any help much appreciated

THanks
 

Trust the gauge inside the car as to what kind of pressure you have inside your pipes. You must have a boost leak somewhere, as to the boost pressure. Thats what happens when you have cold air going inside your engine. Just turn down your boost so you don't hit fuel cut and get a chip burned for your setup. You should be fine.
 

I believe my ECU is already chipped?

Even when my boost gauge is turned down it still hits 20 psi
 

Chipped for your new setup? Do a boost leak test with your gauge inside the cab reading at least 10 psi. Let me know what you find.
 

No problem bro.
So even if the regulator on my air compressor goes higher than 20 psi, but my boost gauge in the cab is at 3-4 psi, its ok to turn the regulator up past? 30 or 40???????
 

Rausch

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^ If I'm reading that right, you have a big leak somewhere.
 

I will def. double check tonight. I lowered the mbc down one click and it is still spiking to 20psi. I also extended the boost controller line about 2feet from the jpipe to the P port.I know its supppose to be shorter, mayb thiis could cause a problem aswell?
 

Rausch

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Joined
Dec 21, 2004
Messages
12,049
Location
Cleveland, OH
How are you doing the boost leak test?
 

Barnes

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Richland, WA
Have you tried setting your boost controller all way down to minimum? I would suggest this just to get a baseline, see if it boosts normally at the low end.
 

I am going to lower MBC lower and see what the reading is.

for boost leak test I remove my iintake from the turbo install the tester. raise regulator psi to 20 for about a minute. turn off aircompressor and listen. I hear air going in the turboinlet, but hear or feel no leaks newhere else. I also tale off the boostcontroller from the P port sinc it leaks and cap it. correct? or no?
 

Barnes

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Joined
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Messages
6,249
Location
Richland, WA
Turn the compressor off? Do you not have an air tank? Just hook up the air line to the tester, set the compressor at 20psi, and leave it alone. You want to have 20psi the whole time you are searching for leaks.
 

excuse me, the compressor is off but air is in the tank but regulator is left at 20
 

So would the boost reading in the car suppose to vary or be the same? even though my boost gauge is tapped off the intake manifold?
 

Even with no leaks if the compressor is at 20 - and you have a hose - you will not be seing 20 at the manifold.

Do like suggested - hook up compressor and turn it up until you get 10 psi on boost guage in car constantly.
Then you should find the leaks (use soapy water)

Also can you bypass the MBC - hook the line directly into the wastgate actuator.
If it still spikes then you know its not MBC.

Are you sure it's boost spike and not boost creep?
Boost spike - Jumps to 20 then comes back down to certain pre-set level level
Boost creep - just keeps going up until it is over desired boost level - stays there as long as turbo can keep it there (May drop if turbo not big enough to keep it up)
 

it hits 20psi and the car backfires and sounds like my engine is throwing rocks at the hood. sorry; bestway u can expplain it lol. Yea it hits 20psi and then I usually let off because the car won't let it
 

ok well I did the boost leak test.and the regulator was at forty and the guage in the car is at zero still!! there still is no hiissing sound aswell!
 

Rausch

Well-known member
Joined
Dec 21, 2004
Messages
12,049
Location
Cleveland, OH
Engine at TDC? I'm wondering if you have valves open...
 

isn't it hard to have a 4 banger w. it all the way to top?

so u think all the valves are open? do I have to set it to 30deg.?
 
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