Twigster Home

MY99 uk turbo, full de-cat, John Banks ecu (tek2.5), samco turbo hoses, K+N induction and no other engine mods to speak of!!

I seem to be getting around 2psi too much boost in each gear, although I suspect this is slightly more once the engine is warm but I haven't pushed it in case I blow her up!!
I have cleaned the solenoid, and checked all the vacuum pipes that seem to split and I can't fing any tears or cracks, so what I am looking for is suggestions as to what may be the cause!! Any ideas?? Checking the downpipe for leaks tomorrow but not sure that would cause it - or would it??
Am checking a new solenoid as soon as Fuzz get's back to me about when to pick it up, so anything I can do in the meantime?


Also, I am currently looking at a set of ported headers (I know they are done properly as I know the previous user), will this need a re-map or will they run with the current map that I have??

Twigster

up...

The_Judge

What boost level are you getting then? And has it only just started to boost to this level, or is it since making a mod? You could try drilling the restrictor out a tad. Or if you're running a 2 port wastegate solenoid, a 3 port might help...

Twigster

I am getting around 17.5 psi in third, 18.5 in fourth and I have seen 17 in second.
Am running the standard solenoid at the moment, but have never had any problems before.
What size should I be drilling the restrictor out to - if I have to at all!!!???
Not made any recent mods to cause this at all!!

The_Judge

If it's only just started doing it, and you haven't made any mods to it recently, there must be something wrong with the wastegate solenoid. When you said you cleaned it, how did you clean it exactly? Did you put ECU into diagnostic mode, remove hoses(s) from solenoid, and spray (lots of) brake cleaner inside? Also the restrictor might be slightly clogged. Spray some brake cleaner in the hose with that in (hose from compressor to T-piece). Don't worry, you won't need to drill it if it's worked OK up until now. Also, what level's your engine oil at...?

Twigster

Engine oil is spot-on, cleaned it as per the above but will try the restrictor as well, although I am fairly sure we cleaned that hose as well!!

john banks

Slacken off the actuator a turn before fiddling with restrictors would be my suggestion.

The boost map is a compromise between cars with just an exhaust and others with air filter and samco hosing. Sometimes you need a small adjustment up or down on the actuator or restrictor to get it to hit boost targets.

It is mapped around a car running standard boost with little overboost with breathing mods already done on the standard ECU. If it overboosts on the standard ECU it will overboost on the mapped one, it is all relative.

Most cars would overboost slightly with your breathing mods.

Twigster

Thanks John, where would i set about adjusting the actuator then?
Also, I am not in any way blaming the ecu as the car has been perfect for the last eight months or so!!
More info if it is relevant though... Over the last two months and at different times I have had exactly the same problems after the vacuum hose from turbo to wastegate (with the restrictor in) split. This happened twice, and I have now completely replaced the pipes and the restrictor (in the correct place before anyone panics!). Could there be an underlying problem which is causing this to happen as well as my current dilemma???

Stevie B

Hi Guys,

Could cleaning the restrictor this way help with my 'Fluctuating boost' scenario you have been very kindly helping me with?

The_Judge

Just replied to that one...

Twigster

Ok, went out and cleaned everything yesterday, no difference and it is still running poorly.
Could the restrictor be in the wrong place in the pipe and would that make a difference???

Also, the idle is moving a little, not much like a Maf failure, but a little (200 rpm or so).
The rev's also seem to jump slightly when I change gear from under acceleration and I am led to believe that this is symptomatic of an air leak. However, I have checked all the usual places with some carb cleaner and haven't found anything.

Any suggestions???

The_Judge

When you replaced the compressor to actuator hose (because of split) did you replace the restrictor with a new one, or did you push the old restrictor into the new hose...?

john banks

Different hose or even slight difference in restrictor "recalibrates" the whole setup which is a very fine balance.

Actuator slackening would help - take downpipe heatshield off (when cold , 10mm spanner)... then release circlip and use 10mm spanner again to release locknut. Loosen the actuator by one complete turn, refit as reverse and try again.

Twigster Home

Pushed the old restrictor into new hose, but I marked out the location for it from the existing one beforehand so I thought it should have been the same.

Thanks for the advice John, much appreciated!

Will strip it all off then have a go this weekend. I am looking at a set of ported headers to go with the current set-up once I get it sorted. Will the map be ok for this or would you advise that I get it 'tweaked'?

john banks

It will be fine with ported headers.

Scott.T

iTrader: (2)

As mentioned above, the hose internal diameter will have an effect if you are not using standard Subaru Hose (i.e Samco or similar).

Also as John mentioned use the actuator adjustment to fine tune if it is of concern.

I played with my restrictor last week as the boost was overshooting quite a bit in 4th. I only 'showed' it a drill bit and it has changed the boost characteristics quite dramatically. In fact I probably need 1 turn on the actuator to bring the held boost back up a bit.

P.S The restrictor should be in the pipe from the Turbo outlet to the T-piece 'NOT' T-piece to actuator.

Twigster

It's in the correct pipe, just not sure if in the right place. However, I will be using all o fyour advice, as well as some new (subaru standard) hosing and parts as soon as they are ordered.
Thanks again for all your help guys!