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[Cexy_Ratt]

You guys must hate me, i am such a newbie to this turbo malarkie.

When i am not moving ie in neutral and i rev my enigne so i get positive boot, the boost gauge i have goes to just under the 0 posisition when revving in neutral is this correct?...

Also what is this waste gate chatter people go on about , i dont think i am getting any , should i be, could this be a problem?

Also in your opinions is petrol a good fluid to use to wash out the IC and is it worh stripping the AFM and cleaning the unit and pipes which go to the turbo. I took the pipe which goes to turbo from the AFM and noticed a small amount of oil setting there, i am assuming this isnt good, altohugh the car boosts to .09 bar ok, i dont wanna go over this so thats fine..

Thanks in advance , rob

Also though it would add, doesnt seem to be using any oil and there is no blue smoke coming out of the exhuast, the exhaust is nice and black on the inside. been readig some posts on the GT4OC which describe the oil in turbo, and it scares me now..

[Fizz]

Right...

When there is no load against the car the boost will not come into play. So revving when idle will not use the turbo and the fact that it goes just below the 0 mark is correct.

When your engine is running and idle, the turbo will be running a vacuum and when on boost it runs the opposite.

You wont get wastegate chatter... as the 3SGTE don’t get it.. :P

No smoke is good news as well. I wouldn’t worry about the oil in the turbo. Only thing to be aware of is after a 'heated drive' never turn the engine off without letting it cool down first.

If you turn the engine off straight after giving it a thrashing you won’t allow the turbo to circulate the oil round it to cool it down. This in turn will cause friction if it starts to 'dry up a little' for lack of a better expression.

Usually a couple of minutes cool down would be suffice OR drive the last couple of miles off boost which would do the same thing.

Cleaning connectors cant do any harm so nothing to loose there.

i have no idea on cleaning the IC but others im sure will be able to help on that.

Hope some of that info was useful if you haven’t heard it before. :)

[Cexy_Ratt]

I am feeling happy now, thanks pal. yeah i have ordered a turbo timer today for it, but have just been smoking a !Removed! whilst it cools down before turing it off or driving gently for the last part of my drive.

right...

When there is no load against the car the boost will not come into play. So reving when idle will not use the turbo and the fact that it goes just below the 0 mark is correct.

When your engine is running and idle, the turbo will be running a vacum and when on boost it runs the opposite.

You wont get wastegate chatter... as the 3SGTE dont get it.. :P

No smoke is good news as well. I wouldnt worry about the oil in the turbo. Only thing to be aware of is after a 'heated drive' never turn the engine off without letting it cool down first.

If you turn the engine off straight after giving it a thrashing you wont allow the turbo to circulate the oil round it to cool it down. This in turn will cause friction if it starts to 'dry up a little' for lack of a better expression.

Usually a couple of minutes cool down would be suffice OR drive the last couple of mile soff bost which would do the same thing.

Cleaning connectors cant do any harm so nothing to loose there.

i have no idea on cleaning the IC but others im sure will be able to help on that.

Hope some of that info was useful if you havn't heard it before. :)

[daktari]

Exactly as Fizz says

Cleaning the IC. Remove from car, Plug one end and fill with a bit of petrol. Not right up cos you want to be able to slosh it around Plug the other end and agitate vigorously for a minute or so. Empty and repeat until petrol coming out is clean. Job done.

[Fizz]

You might be better off getting an after market boost gauge as well due to the fact that the factory ones are CRAP. Very unaccurate. :)

[Cexy_Ratt]

I have a Tim gauge fitted, goes up to a bar. Is tim any good as a manufacturer of gauges, i am guessing prob not, as they are only about £30

You might be better off getting an after market boost gauge as well due to the fact that the factory ones are CRAP. Very unaccurate. :)

[daktari]

I have a Tim gauge fitted, goes up to a bar. Is tim any good as a manufacturer of gauges, i am guessing prob not, as they are only about £30

Certainly better than the standard one.

[Fizz]

In all honesty, any mechanical gauge will do the same job.

One question though.. i thought that the standard boost on a 185 was 10Psi? Now is 10 Psi .9bar?

Can somone correct me if im wrong as the ST205 has the revision 3 engine which is 13psi as standard.

[Cexy_Ratt]

10 psi is 0.69 bar, so at 0.9 bar i am boosting to might reduce it a little

[Fizz]

10 psi is 0.69 bar, so at 0.9 bar i am boosting to might reduce it a little

Thats what i thought. Do you have any type of boost controller in place that you are aware of? Either an electronic or Manual one?

[Cexy_Ratt]

It has a manual boost controller in the car, has to be wound out quite a bit to make the boost go up to 0.9 bar though

10 psi is 0.69 bar, so at 0.9 bar i am boosting to might reduce it a little

Thats what i thought. Do you have any type of boost controller in place that you are aware of? Either an electronic or Manual one?

[Sketchy]

What people tend to be talking about when they say wastegate chatter is the fluttering noise when you come off the throttle when on boost.

This name is infact inacurate as it's actually compressor surge. The noise is made by air forcing it's way back past the compressor when you come off throttle. Only happens on cars without dump valves.

Basically when you come off throttle the revs are still high and the turbo still spinning the boost in the pipes thus increases until a point where the air pressure in the pipes overcomes the air being force into the pipe by the compressor and the air forces it's way back out through the compressor and creates the chattering noise as the air is "chopped" by the compressor blades.

It also effectively stalls the turbo and thus it takes longer to come back to full boost when you reopen the throttle

It very popular with the cossie/rs turbo crowd.

Sounds cool but eccentually very bad as it puts extra stress on the turbo bearing and generally reduces the life of the turbo significantly.

A dump valve is designed to avoid this.

An it can happen on a 3sgte fizz just not many people have the money to pay for the regular turbo rebuilds so we all get dump valves instead. With the stock intake you won't be able to hear it but with a induction kit and modest boost i.e. about 12 psi just block off the dump valve vaccum line and you get it.

[Fizz]

Right.. I have cleaned up this thread as i took it off topic. *sorry

I have created a new thread relating to the posts about my dump valve issue. :)

[johndgt4]

Some oil in the pipe may be coming from your PCV (positive crankcase ventilation) system which routes back here and is normal. Get an oil catch can on there to prevent a lot of this going back into the engine to get burnt. But do not vent this to atmosphere on a 185 as you'll get all sorts of problems, just plug it inline.