Hi people,

Got a 4x4 saph cossie that has developed a problem!
Was driving along earlier not really booting it got to maybe 80 in fifth and car was hesitating big time to boost more..
Its 350bhp and peaks at 1.7 bar on the gauge so really strange?

Anyway next thing is the turbo gauge doesnt move and the dump valve stops working?

Have checked all pipes on turbo, no oil in them, no pipes come off or loose, no oil over the engine or anything, dump valve is all connected fine as are the links to the boost gauge???



Any ideas??/


Its driving me mad!!

Thanks in advance..


Dave.

 

btt anybody got any ideas?

 

dump valve diaphragm ?

 

Just changed it yesterday and it worked fine? cant understand it shouldnt have gone again surely??

 

Hi m8,

Is your dump valve on the warm side or the cold side of the intercooler? Mine used to get through the diaphrams big style when on the warm side (near the intercooler)

Is it making any boost at all?

It could be a faulty actuator or pipes to and from actuator.

Also could be faulty amal valve.

More info on symptoms please


JJ

 

Hi mate..

Yeah its on the warm side, just replaced the dia too. just checked it and it hasnt split again so that aint it..

It is still pulling but is hesitant in places esp top end in fifth? sometimes misfires on boost occasionally then it clears and its fine agian 99% of the time?

Dave.

 

Hi m8,

out of curiosity it may be worth checking fuel supply. Different car I know, but my mates Skyline was doing exact same thing as yours, and needed a fuel filter. Replaced filter, good supply and all was well with the world!

This wouldnt explain the misfire though - may be worth having it checked by a friendly local garage to ensure that it is not running lean, else small problem could become big problem!

Cheers

JJ

 

Okay a bit of an update...

just taken it out and it doesnt seem to be boosting at all?
turbos spinning and that just no boost and turbo gauge isnt moving??

Its doing my head in!!

any further help appreciated???

cheers jj will def get it checked mate.

Dave..

 

Hi mate

Out of curiosity, I assume your boost gauge would normally show vacuum as well as boost?

If so, when you have engine on and no throttle, it is running on vacuum, like a naturally asparated engine. If the engine is off, then it should be centred at 0. If the needle is not moving at all, then it is a good chance that you have a breach on your pipe connecting the boost gauge to your plenum.

Is the above the case? If so, trace the pipe back to plenum, unplug and seal, and try again. If this is the case, then you know the problem is either in the gauge or pipe to it (more likely).

Let me know if the above symptoms are correct, or if it is just not making postiive boost, which could be many other things

JJ

 

Hi Mate,

Yeah it does show vaccum as well, but it stays centred at 0 all the time inc when off and start up and driving. Doesnt move one bit even when putting foot down mate??


Dave.

 

Souds to me like the gauge isnt getting the correct information from the plenum.

In the best case, this points to a leak somewhere around the plenum, which explains the symptoms, as well as the boost gauge problem

Check really carefully around the plenum and inlet for leaks, and pipes that are off/ loose/ broken. With boost gauges, often the supplied plastic pipe can become brittle. Take it off and block it to test.

Just athough, but if this is 'T'd off a pipe that tells the ECU when to make boost etc, it may be defeating the boost on the wrong info. Check really carefully all the small pipes that go to the various bits on the inlet side, including the Map sensor (upside down on plate on inner wing), the Fuel Regulator (really important one, this one, can make engine go bang if loose!) and all others!

Could also be fucked gauge, but unlikely as you have other symptoms as well!

Let me know what you find

JJ

 

Okay mate will have a look at those, thanks for your help..

Where do i find fuel regulator?? bit naive when it comes to that sort of thing



Dave..

 

Hi mate,

Take a look at the inlet side. The injector rail is the stainless steel thing sitting on top of the injectors. On the end of this (close to the front of the engine bay, you will see a thing that looks like a small barrel (very small), which has a fuel pipe (return) coming out of the bottom of it (don't touch this!), and a air line coming into it horizontally at high level.

The air lines are pretty easy to identify. Dont get the fuel lines confused though!

If you didnt install the boost gauge, the pipe that looks like it is leading away from the engine to the rear will be the one you are looking for. (ie towards the cockpit). Also check pipe to top of dump valve.

JJ

 

Thanks mate your a star.. will have a look 2m and let you know what i find!

Thanks for your help, much appreciated.

Dave.

 

No worries mate!

I will keep an eye tomorrow for your posts for progress!!!!

JJ

 

Turbo shaft snapped ? take pipe off that goes to the air filter to turbo, is the nut still on the end of the shaft?

 

SORTED!!

Was a pipe from gauge to plenum come loose!!

Thought I was in for big money spend for a bit there

Thanks to you all for your help esp JJ...


CheeRS

Dave.

 

Thought so!

Glad to hear that it is all working mate!

Cheers

JJ