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- - Boost cut 0.5 bar (https://www.scoobynet.com/general-technical-10/1054408-boost-cut-0-5-bar.html)

Scoob1000

24 May 2018 01:40 PM

Boost cut 0.5 bar

Hi folks car is cutting boost at 0.5 bar low boost and 0.8 bar high boost,so I took the pipe off the actuator and see if boost increased which it did,brought the car back to life,only done one boost blast,put the pipe back on and she’s back to 0.5 bar, cars mapped decatt apexi filter MY95 any ideas what it could be? Seems I’m running actuator pressure only

The Rig

24 May 2018 06:26 PM

Standard boost solenoid ?

Could be stuck closed

If so try cleaning it, run diag mode to set the solenoid into rapid fire and quirt with wd40

Scoob1000

24 May 2018 06:36 PM

Quote:

Originally Posted by The Rig (Post 12011143)

Standard boost solenoid ?

Could be stuck closed

If so try cleaning it, run diag mode to set the solenoid into rapid fire and quirt with wd40

yes standard 3 port,tried cleaning and hasn’t made any difference,I’ve got an Alcatek ecu can I run diag with that ecu

Scoob1000

25 May 2018 09:46 PM

Just an update,tested the actuator and is working as it should,no boost leak,took dump valve off just to eliminate that,drove the same,0.5 bar on low boost and 0.8 bar in high boost,ordered a boost control solenoid to eliminate that.so frustrating as it’s not driving as it should,

The Rig

27 May 2018 01:37 AM

If you simply removed the vaccuum line going to actuator and left it disconnected you will indeed get full boost as the actuator isnt getting any pressure so will stay closed which would give full boost, 1.5 or so if boost cut didnt kick in.

what you needed to do was plumb the turbo outlet line direct to actuator and see if it was a steady 0.8 or so.

Does sound like solenoid is playing up tho

Scoob1000

28 May 2018 09:00 AM

Quote:

Originally Posted by The Rig (Post 12011389)

thanks mate,ok so the turbo outlet line which is connected to boost solenoid and connect that to actuator right?

The Rig

29 May 2018 02:55 PM

Hi Bud,
yes, the line that comes from the turbo outlet goes direct to actuator to test

Cheers

Scoob1000

29 May 2018 03:27 PM

Quote:

Originally Posted by The Rig (Post 12011641)

Hi Bud,
yes, the line that comes from the turbo outlet goes direct to actuator to test

Cheers

ok mate thanks,I’ve taken the solenoid out now I read this reply today, When you blow through the top feed and side feed it lets air but the bottom feed that goes to air filter intake is closed you can’t blow through it, is that right? I haven’t got new solenoid yet hopefully get it tomorrow,

The Rig

29 May 2018 05:52 PM

yeah thats rite, basically the 2 you can blow through are basically boost in and boost out, the 3rd to airbox is what regulates the flow, so as you found out its currently fully closed which means all turbo pressure would go to actuator hence only safe boost ( you have simulated if the solenoid lost power if it were all plumbed in still)

Scoob1000

29 May 2018 06:31 PM

Quote:

Originally Posted by The Rig (Post 12011677)

Thanks for all your help buddy,so the boost solenoid is the culprit then I take it

The Rig

29 May 2018 10:12 PM

Hi bud

It still could be but by removing power it defaults shut as a safety precaution so this method of testing can't say if the solenoid is faulty

Scoob1000

30 May 2018 01:25 PM

Thanks mate,new solenoid arrived today fitted it with new piping,took it for a test drive and it’s still the same if not worse,could feel a stutter whilst driving,it idles steady but revs are very low then when I press accelerator it wants to cut.i don’t know what to do now,changed plugs,coils (newage)fuel filter,fuel pump,cleaned icv checked for boost leaks none found,compression test was ok, is there anything else left that I could try/test

The Rig

31 May 2018 01:50 AM

Have you joined the 2 green connectors together for any fault codes ?

Scoob1000

31 May 2018 08:19 AM

Quote:

Originally Posted by The Rig (Post 12011944)

Have you joined the 2 green connectors together for any fault codes ?

haven’t tried that,would it still work with Alcatek ecu installed.

Thanks

The Rig

01 June 2018 10:10 PM

Hmmm not sure, not familair if they alcatek still retains the original check engine sequence or its own check codes.

what exactly is happening then, im confused by the original post now i read it back, you get 0.5 at low boost and 0.8 at high boost, is this a setting within the alcatek you can select as my low boost is less gas pedal or high boost is more gas pedal lol ha

Scoob1000

01 June 2018 10:45 PM

Quote:

Originally Posted by The Rig (Post 12012235)

Hi mate,I have 2 boost settings low boost and high boost,both switch over fine when switch flicked, so when I’m driving on low boost I’ll get 0.5 bar and then boost cut,when I go to high boost it will only go to 0.8 bar then boost cut won’t go any higher,the pull isn’t there anymore,Spoke to the mapper he said that nothing to do with mapp look at other things,and boost seems very low we wouldn’t have left it like that.,When I got the car it was boosting a lot higher in both maps and pulling like a train which you could feel.

hope that helps.

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