Boost Leak

[ford number 1]

I had the same thing happen to me.Just after my car was on dyno I was driving home when boost gauge went to zero and I lost power.I checked all the connections(hoses etc) and couldnt find anything loose.I then reflashed back to standard and then back to the map and the power was back..Seemed very weird..

The only other thing I checked while loading the tune back in was the nylon tubing for the boost gauge..

[Terebro]

The leak DOES sound like its coming from right behind the guages.

I initially thought it was from the passenger side, but it seemed to be more centre.

When I turn the car off, I hear a more high-pitched wooshing sound as the engine cuts. This sounds like its from the top of throttle body, or behind the guages against the firewall.

Ive checked all visible hoses around the throttle body and none have come off. It might be a split, but I wouldnt think a small split would make such a loud noise.

Certainly sounds like an entire hose has come off the noise is that noticeable.

Edited 26/04/06 02:00 AM by Terebro

[Paradoxx]

Is the BOV working properly? The small hose on it holds the piston closed while under boost, but if this is loose or broken the BOV will vent all of its pressure immediately. Check the small hose and any tee pieces you have in there, and anything else that is attached to this (gauge?) as if there is a leak here the BOV will not hold pressure.

[Dagabond]

  XXXR6T said:

Is the BOV working properly? The small hose on it holds the piston closed while under boost, but if this is loose or broken the BOV will vent all of its pressure immediately. Check the small hose and any tee pieces you have in there, and anything else that is attached to this (gauge?) as if there is a leak here the BOV will not hold pressure.

←

Hasnt blown the gut's out of the BOV has it...

[Paradoxx]

Highly unlikely... the bosch BOVs are tuff as nails (ran 22psi with one and no problems)

[Terebro]

I physically removed the small tube from BOV to brass Tpiece and it was 100% like brand new and fastened properly.

Im thinking its the guage.

[Paradoxx]

There's your problem then, the gauge musn't be holding that pressure. Try blocking off the gauge hose or remove the tee piece from the line and see if you get boost back.

[Xtreme F6]

  XXXR6T said:

There's your problem then, the gauge musn't be holding that pressure. Try blocking off the gauge hose or remove the tee piece from the line and see if you get boost back.

←

the gauge not working or leaking isnt going to not give him boost, its just a gauge and that little iddy biddy line isnt going to loose 18 pounds out of it.

nor would it leaking be enough for the BOV to stop working I wouldnt have thought.

Edited 26/04/06 02:39 AM by Xtreme F6

[PSYCHO XRT]

  Terebro said:

I got my tune done today and on the way home I came off throttle and heard what sounded like a loud aftermarket BOV coming from in front of the passenger seat.  From then on I have no power and whenever the turbo spools I hear a loud 'wooosh' sound from the passenger side.

It was on the dyno an hour earlier so I double checked the boost pipe to see it was put on properly to the BOV and its fine.  Its connected to the T piece fine also.

I couldnt get under to see if the intercooler hose had come off or was loose, but we replaced the hose clamp just on friday - and the sound DEFINITELY comes from the passenger side, near the BOV.

Considering the BOV hoses are connected, does anyone have any ideas what can be causing this massive boost pressure leak?  It was getting 16-17 psi on the dyno (and has been around that for the past 3 weeks) and now something has given and I can't see what it is.

Any ideas?

←

I had the exact same problem about a month ago. Also lost heaps of pwr, and factory blow off valve sounded like an aftermarket one aswell.

XXXR6T was very helpful by telling me to check the pipes, bov etc etc.

I did that but everything seemed to be fine.

How did I solve this problem???

I simply re-flashed it back to factory and then reloaded my tune and 'YES' PROBLEM SOLVED.

Give that a try mate.

[Paradoxx]

  Xtreme F6 said:

  XXXR6T said:

There's your problem then, the gauge musn't be holding that pressure. Try blocking off the gauge hose or remove the tee piece from the line and see if you get boost back.

←

the gauge not working or leaking isnt going to not give him boost, its just a gauge and that little iddy biddy line isnt going to loose 18 pounds out of it.

nor would it leaking be enough for the BOV to stop working I wouldnt have thought.

←

I know I'm no boffin on hydraulics, but from my understanding it doesn't matter what size the hose is, if it doesn't hold pressure then the BOV won't work and it will bleed most or all of its boost. Since the Gauge is attached to the same line as the actuator hose for the BOV this hose needs to be completely sealed for it to provide the pressure on the piston in the opposite direction to the pressure in the crossover plumbing. If there is a leak from the small actuator hose then the pressure on the big side of the BOV is larger than the other side of the piston forcing it to open. I figured since the pressure in the actuator hose and the gauge hose are effectively the exact same pressure point (much the same way electricity works with voltage) then if the gauge is broken or there is a leak in this hose it will not hold.

But as citric suggested try re-flashing it.