FIXED!! Intermittent Boost leak?! Tried everything!!
#1
FIXED!! Intermittent Boost leak?! Tried everything!!
Ok i'm hoping for some good idea's here as I have tried everything I can think of!
This is an intermittent fault so sometimes it's fine other times it's not but it will do it everytime I drive so it's a problem that needs sorting!
Start accelerating and as the turbo spools up it will not hold boost, the boost gauge needle will flap around something crazy, the car will splutter, backfire and jerk around as the boost tries to increase but doesnt in a on/off type fassion.
It feels like a boost hose has come off or there is a big boost leak some where?!
The car is MFI with Bailey breather setup and metering unit return blocked venting to atmosphere, I have tried.........
Removing every boost/vacuum hose and checking for splits, twice! (all hoses are Samco and done about 5000miles).
Brand New Turbo/Manifold/Garrett -31 Actuator.
Brand New Apexi AVC-R Boost controller (fault is still there if i remove it and pipe turbo direct to actuator).
New NMS Head.
2x Different Cam/lifters (one was a brand new set and ran in properly).
New Plugs, leads, Dizzy Cap, Rotor Arm, Dizzy, Coil, ECU's (Ignition and Fuel).
New Fuel Filter.
Voltage to Coil and Fuel Pump is 12.5v.
Timing.
Disconnecting boost gauge.
No Dump Valve.
So i'm left thinking, cracked inlet manifold, charge carrier pipe, throttle body, or maybe an injector not seating correctly?
Any and all idea's greatly appreciated!!
This is an intermittent fault so sometimes it's fine other times it's not but it will do it everytime I drive so it's a problem that needs sorting!
Start accelerating and as the turbo spools up it will not hold boost, the boost gauge needle will flap around something crazy, the car will splutter, backfire and jerk around as the boost tries to increase but doesnt in a on/off type fassion.
It feels like a boost hose has come off or there is a big boost leak some where?!
The car is MFI with Bailey breather setup and metering unit return blocked venting to atmosphere, I have tried.........
Removing every boost/vacuum hose and checking for splits, twice! (all hoses are Samco and done about 5000miles).
Brand New Turbo/Manifold/Garrett -31 Actuator.
Brand New Apexi AVC-R Boost controller (fault is still there if i remove it and pipe turbo direct to actuator).
New NMS Head.
2x Different Cam/lifters (one was a brand new set and ran in properly).
New Plugs, leads, Dizzy Cap, Rotor Arm, Dizzy, Coil, ECU's (Ignition and Fuel).
New Fuel Filter.
Voltage to Coil and Fuel Pump is 12.5v.
Timing.
Disconnecting boost gauge.
No Dump Valve.
So i'm left thinking, cracked inlet manifold, charge carrier pipe, throttle body, or maybe an injector not seating correctly?
Any and all idea's greatly appreciated!!
Last edited by Karlos G; 04-05-2009 at 10:51 AM.
#2
Part of the Furniture
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You could make up a bung to put onto your inlet where your air filter goes and try pressurising the system, i just used a bit of metal tubing the correct diameter, welded a plate on the top drilled a hole through the plate and super glued a bit of inner tube with the valve in the hole, has worked upto a 18 psi so far, nice easy way of checking for leaks. just hook a compressor up to it and away you go.
Alex
EDIT: hope that makes...
Alex
EDIT: hope that makes...
Last edited by capriturbo; 01-05-2009 at 05:41 PM.
#5
I've found that life I needed.. It's HERE!!
The ONLY way to find leaks is to spray easy start around your engine when its running if the idle speed increases you have a leak. Worked great for me.
#7
Wahay!! I've lost my Virginity!!
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You could make up a bung to put onto your inlet where your air filter goes and try pressurising the system, i just used a bit of metal tubing the correct diameter, welded a plate on the top drilled a hole through the plate and super glued a bit of inner tube with the valve in the hole, has worked upto a 18 psi so far, nice easy way of checking for leaks. just hook a compressor up to it and away you go.
Alex
EDIT: hope that makes...
Alex
EDIT: hope that makes...
http://www.youtube.com/watch?v=atretf9u-Mc
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#8
You could make up a bung to put onto your inlet where your air filter goes and try pressurising the system, i just used a bit of metal tubing the correct diameter, welded a plate on the top drilled a hole through the plate and super glued a bit of inner tube with the valve in the hole, has worked upto a 18 psi so far, nice easy way of checking for leaks. just hook a compressor up to it and away you go.
Alex
EDIT: hope that makes...
Alex
EDIT: hope that makes...
This probably makes more sense. Its Australian but a good vid.
http://www.youtube.com/watch?v=atretf9u-Mc
http://www.youtube.com/watch?v=atretf9u-Mc
A pressure test is a very good idea though so i'll probably do that next.
#13
Too many posts.. I need a life!!
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Thats no good, the std setup has the pipe going to the metering unit for a reason, it runs on a vacuum system, venting your bailey breather to atmoshpere is like i said before, its like running with your oil filler cap off or a breather pipe off.
#15
But it's blocked so there is no air leak.
#17
Ok after further testing it seems that if I put my foot flat to the floor in any gear then the problem stops immediately, if I lift off even a little then it will start again.
So i'm thinking it's not a boost leak or it would still continue whether my foot was down or not!
That leaves ignition and fuelling, seeing as I have replaced nigh on the entire ignition system i'm thinking maybe my metering unit is at fault?!
So i'm thinking it's not a boost leak or it would still continue whether my foot was down or not!
That leaves ignition and fuelling, seeing as I have replaced nigh on the entire ignition system i'm thinking maybe my metering unit is at fault?!
#27
Advanced PassionFord User
a simple test for you to try, run the boost set up as ford intended pipe wise and set your pre load on your actuator with a foot pump to read 6 psi then try that as it will rule almost everyting out
#28
The boost setup is piped as Ford intended I just have my Apexi in place of the Amal valve, i've tried it without and makes no difference. Preload is about 7psi as this is what boost it holds mate.
I'm thinking it's a metering unit fault as when my foot is planted it's fine, when I lift off slightly the problem starts again......... When my foot is planted the TPS signals the EMFPA to increase fuel pressure for full load and all is well, when I lift off it fuels only based on the air flow (flap being sucked down) and that is when i'm having the problems.
I think my EMFPA might be fucked so i'll try another one tomorrow and see what happens, if not then the metering unit itslef which I also have a spare to try.
I'm thinking it's a metering unit fault as when my foot is planted it's fine, when I lift off slightly the problem starts again......... When my foot is planted the TPS signals the EMFPA to increase fuel pressure for full load and all is well, when I lift off it fuels only based on the air flow (flap being sucked down) and that is when i'm having the problems.
I think my EMFPA might be fucked so i'll try another one tomorrow and see what happens, if not then the metering unit itslef which I also have a spare to try.
#30
Too many posts.. I need a life!!
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Nice you have problem sorted, i next would recommed efi conversion if you cannot find problem
Last edited by Antti O; 04-05-2009 at 11:25 AM.
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