R33 Skyline Only Reaching Half Boost

[Dobby525]

My r33 is only reaching half boost pressure I have a gizmo ibc ebc if I have it on the 4th setting which is 12 pound it will only rise to 6 pound and if I have it on setting 1 which is 7 pound it on reaches about 3.5 pound it was working fine up untill a few nights ago and it just went pear shaped and it has been a little bit rough on idle any ideas what it could be?

[Anfanee]

Could be heaps. Could be the boost controller going. Try disabling it completely. Do you get wastegate pressure? Mine was doing that and it was just the boost controller was farked. also could have a cracked vacuum line or a number of things.

[Ricky_Bobby]

Sounds like you have a vacuum line leak to me mate , havent seen many gizzmo products fail over the years and from what your describing it sounds just like a vacuum leak like Anfanee says.

Edited January 8, 2013 by Ricky_Bobby

[Dobby525]

I won't put and bought some new vacuum lines today will wait till later to put them on too hot ATM lol thanks guys for the fast reply.. Could it be also a leaking injector?

[Dobby525]

Only reason why I ask is cause their is a smell of petrol occasionally coming through the aircon vents

[Dobby525]

All good guys found it in the daylight was the vacuum hose going from the bov to the boost gauge

[89CAL]

My r33 is only reaching half boost pressure I have a gizmo ibc ebc if I have it on the 4th setting which is 12 pound it will only rise to 6 pound and if I have it on setting 1 which is 7 pound it on reaches about 3.5 pound it was working fine up untill a few nights ago and it just went pear shaped and it has been a little bit rough on idle any ideas what it could be?

Stock actuator will not allow the car to hit this low a boost level. There is either a boost leak somewhere or your boost gauge is faulty (I'm not sure if your reading boost on the Gizmo or on another boost gauge)

[Kinkstaah]

I had a similar problem on my car (before it expoded - not related!) and never found the problem in regards to it..

Where boost would never (ever) reach the level set by the EBC - 100% confirmed it wasn't an exhaust or intake restriction (as I had removed them) and 100% positive the Vac lines were running correctly as they were checked and re-checked and hose clamped and such.

Also confirmed the boost controller was actually working as I could hear it 'ticking' - What on earth could feasibly cause that kind of behaviour at that point?

[Ricky_Bobby]

All good guys found it in the daylight was the vacuum hose going from the bov to the boost gauge

No dramas pig farmers

[Akshunhiro]

I had a similar problem on my car (before it expoded - not related!) and never found the problem in regards to it..

Where boost would never (ever) reach the level set by the EBC - 100% confirmed it wasn't an exhaust or intake restriction (as I had removed them) and 100% positive the Vac lines were running correctly as they were checked and re-checked and hose clamped and such.

Also confirmed the boost controller was actually working as I could hear it 'ticking' - What on earth could feasibly cause that kind of behaviour at that point?

You've got me worried now. You say it's not related to engine exploding but didn't find what the problem was.

I'm having the same problem with mine, it doesn't want to make boost but can hit 12psi with the vacuum line pulled off the wastegate actuator.

I'm trying to rule out vacuum leaks and also checked play on the wastegate flap and it is tight against the housing. A friend mentioned the spring in the actuator could be buggered and is opening simply with exhaust pressure.

[Kinkstaah]

You've got me worried now. You say it's not related to engine exploding but didn't find what the problem was.

I'm having the same problem with mine, it doesn't want to make boost but can hit 12psi with the vacuum line pulled off the wastegate actuator.

I'm trying to rule out vacuum leaks and also checked play on the wastegate flap and it is tight against the housing. A friend mentioned the spring in the actuator could be buggered and is opening simply with exhaust pressure.

At least I didn't think it was related to the engine letting go. In my case I was talking about a 20k+++ forged stroker build which had no rhyme or reason to let go at the boost levels it was producing. I could set the boost controller in the ECU to free boost and set it for 250 PSI and just pin the WG closed and it'd never make more than about 20 psi, and could never really find out why... maybe it'll magically not occur after the rebuild but layman as I am I was kind of out of ideas as to how this could occur.

Mine would be "OK" on wastegate pressure and hold 18 or so PSI, but itd only make 21 or so with the EBC, even when I set it to some ultra retarded high value.