Jump to content
SAU Community

Recommended Posts

Hey guys.

Some of you may know I been stressing over if I have a vac leak or not and after hooking up a compressor I couldnt find anything.

Finally decided to give the car a beating today after getting my clutch sorted and I had a strange issue.

Seems in 2nd where it used to build up 20psi very quickly is only building up to around 18 and is pretty sluggy.

Once I get it into 3rd it makes 20 psi still.

Just seems odd as it's running straight off the actuator which is a 20psi spring

Any ideas would be appreciated

Link to comment
https://www.sau.com.au/forums/topic/408445-boost-difference/
Share on other sites

Already Smashed out ages ago

I have tried the pressure test and tried blocking off all the parts air was coming to but couldn't find anything.

Also checked all the cooler piping.

I wish some in the ACT had a smoke tester because that would be perfect

Already Smashed out ages ago

I have tried the pressure test and tried blocking off all the parts air was coming to but couldn't find anything.

Also checked all the cooler piping.

I wish some in the ACT had a smoke tester because that would be perfect

Autotech do I believe.

Think about what boost is, and what determines boost. This leaves you with a handful of possibilities:

Leak in intake

Faulty BOV

Faulty actuator

Faulty boost controller

Blocked exhaust

Then on the unlikely possibility it's the turbo at fault:

Faulty waste gate flapper

Could also be faulty boost gauge showing wrong when nothing has changed.

Nah you can hear it whistle when around about -40 to -50 vac

also still has a whine noise when on boost.

You can also notice it is lacking in power.

Jez has told me to make sure the turbo is secure which I will check as soon as I get home.

Also will check all the bolts on the exhaust.

When you stick your head in the engine bay and rev it real hard you can smell exhaust fumes but unable to determine if thats just blowing back from the exhaust or not.

But yeah checking all the bolts and will report back

Yeah the turbo dump was a little loose.

We did them and checked the turbo bolts but they seemed fine.

Took it for a spin and it was boosting fairly well.

2nd gear seems to make boost different to when in 3rd which I didn't think was possible.

On the way to work it still managed to whistle again at around the same vacume.

Not sure if related but I cleaned the AAC and put that back on plugged it all back in and no matter what I do the car idles at 1500rpm unless I unplug it

Maybe the AAC hose is damaged? there was a thread like 3~4 years back where one guys' AAC hose (from the cross over pipe) melted and couldn't work out why it was running like shit. Turns out the underside melted because of his turbo.

Just a though :)

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now


  • Similar Content

  • Latest Posts

    • What can't be done with a little bit of decking board or similar timber bolted to a hub flange via 2 wheel nuts is not worth talking about.
    • I noticed something. On the tps sensor and the sensor behind the adjustment screw is adjusted towards the far left. Are these screws supposed to be centered? (this sensor was in the same position before the tune as well)  Also attached a photo of where my car usually idles at when warm (sometimes a tiny bit above that). I think I might have screwed up the calculation and it might have better than I thought lol at 750rpm still not 650rpm though.      
    • So for both general interest of engine health, and to rule out any coolant/oil issues, I organised an oil analysis done on the 125,000klm oil Results below, all good, just a bit of fuel dilution which I'm not too worried about
    • This is actually a really good way of measuring what wheels fit. If only there was a similar measurement between hub face and suspension :p That said, it's probably pretty simple to actually measure it all with the wheel off the car for the rear. The front is a bit more complex but.. 
    • Being the top Google search result for R34 wheel-related inquiries, lemme throw down my experience. I calculated that 100mm from hub face to wheel face is about the perfect fitment for my ENR34 sedan.  I've been running 18x8.5s, ET35, with a 1" spacer. So, 8.5in to mm = 216mm. 216/2 = 108mm. 108-35 = 73mm. 73+ 25 (1" to mm) = 98mm.  If you wanna get close to this on dif widths, here are the offsets you'll want: 9" - ET around 15mm 9.5" - ET around 20mm 10" - you're crazy, but ET around 30mm All these should fit perfectly on a non-widebody, non-GTR Skyline. Note that it's probably the absolute max, and you're probably better off running a couple degrees of camber in this config, but it looks great, super flush.
×
×
  • Create New...