38 replies to this topic

[PeeKay]

Hey guys,

 

First post! 

 

I bought this car from yann  in May 2014 - link to one of his threads: http://www.subyclub....sensor-failure/

 

Have had CEL be thrown whenever I build revs in 4th or 5th gear meaning that I start revving at 2000 and at around 4000 it stops boosting and I get the CEL. I also get secondary turbo boost cut. Today at a meet got a mates OBD2 reader out and it read fault code p1241. 

 

This doesn't happen in any of the other gears. And if I boos all the way through 1st 2nd 3rd and 4th it does not happen, only building the revs up.

 

I've done a search and found a thread but it didnt really explain what the issue was and how it was resolved. 

 

Should be noted I'm quite nooby so any help is very much appreciated. 

 

Also, I'm taking the car to Ichiban next weekend to get the coilpacks changed so will ask them about this too.

 

Thanks,

PK

[glenisanutter]

Hey mate

I have a set of factory B4 coil packs i can do you at a good rate! plus i can install them for a reasonable price!

4th and 5th gears is when the engine is most loaded. unfortunately it could be something simple like a vac line  to something as hard to find as a vac line leak!! 

[duncanm]

FSM says likely to be a solenoid, or as above, vac line leak.

 

 

Attached Files

•  P1241_diagnosis.pdf   141.91KB   64 downloads

[WillC]

A little more insight. Met Peekay last night at a Hills meet with Jonno. His car is N078AD, I'm pretty sure it's been floating around here for some time now. I can't remember who built it but I remember it was one of us. The boost solenoid has been replaced and a profect B EBC in addition to a Turbosmart MBC has been installed as the new boost control system. I suspect this is the goer as the problem.

[PeeKay]

Yup would love any help on this.

 

In this post a member installs dual MBC, one to the primary and the other to a solenoid. Its near the bottom... 

 

http://www.uklegacy....ost controller

 

And in this article there is also mention of a dual MBCs 

 

http://www.autospeed...etter-B4&A=1712

 

So I think there may be a way to have them running, just mine isnt properly...

[PeeKay]

Paul Brell is the Mech who worked on the B4 in the article above. Quick search on google lead me to Boss Tuning - http://www.bosstunin...m.au/index.html

 

Trying to get in touch with him, let me know if anyone has exp with them

[skillionaire]

Hi,

The NSW lads recognised this, they'll be back in Sydney in a couple of days.

Cheers,
Nik

[PeeKay]

Awesome thank you

[PeeKay]

Bump.

[allpaw4]

Mmmm. Fairly likely that the new boost control is what is causing the issue - although that error code is going to be pretty generalised (it basically says there is something wrong with the primary workings of the TT system). If boost control is now being done by the Turbosmart MBC rather than the ECU, it will throw a hissy fit, hence the code. If the ECU doesnt see things happening as it thinks they should, it'll throw codes until the problem is fixed and ECU reset. See what the other boys reckon, but the TT systems are awfully fragile in terms of what will throw codes.

 

Best of luck man.

 

Cheers,

Ben

[Jimbo]

I would get rid of the MBC's on a TT and let the ECU do it itself. The boost they run stock is pretty much as efficient as they're gonna get.

The TT system doesn't respond well to aftermarket boost controllers of any kind. Especially the later ECU's such as what you have on the B4.

[PeeKay]

I would get rid of the MBC's on a TT and let the ECU do it itself. The boost they run stock is pretty much as efficient as they're gonna get.

The TT system doesn't respond well to aftermarket boost controllers of any kind. Especially the later ECU's such as what you have on the B4.

Yup planning to organise some time with my mates stock b4 and try to take everything back to as it was. Would love a couple pairs of extra hands if anyone on here is up for a b4 fixing session with beer supplied

[PeeKay]

Yes sure does. Makes things a little easier space wise.

Going to start ordering vac lines etc. and hopefully return it to stock. I've read the 'your guide to twin turbo' thread but if anyone has a more user friendly diagram of the vac line connections (possibly colour coded) of the stock system I'd really appreciate it. Searched on Google and found a couple but more trusting of you blokes.

Thanks
Pk

[zanzarah]

http://www.subyclub....0499-black-box/

#5

[PeeKay]

http://www.subyclub....0499-black-box/
#5

Perfect! Thanks Zanzarah

[PeeKay]

Hi all

How do I access my vacuum tank and make sure it is functioning correctly?

[duncanm]

'functioning' - means it doesn't leak.  It is literally a bottle with one hole.

 

Its under the LHS front wheel arch (as per the diagram pointed to). Pull the plastic guard if you want to get to it, but I wouldn't bother yet.

 

Vac line comes across the front bumper (two hard lines at the corners, and some rubber in-between).

 

Pull that line where it enters in from the RHS wheel arch to the black box. Then check it holds vacuum or pressure.  If it doesn't, work your way around to the tank.

[PeeKay]

Cool thanks Boss and Duncanm.

 

The reason I think its the vacuum tank/lines is because as I move up the gears from low revs the VoD gets larger. So in first gear building up there is no VoD, in second building up its noticeable but maybe 100-200 rpms, and in third building up larger yet. I've never got past VoD building revs in fourth. 

 

Also just before going into VoD in fourth and fifth it makes a very high pitched squeak/whistle, but doesnt sound like a boost leak.

 

So I have ordered vac lines 3mm in diameter with 2mm wall thickness as recommended in other threads and will set out to get rid of the mbc and ebc and change all the lines including BBoD. Not 100% on how to clean the solenoids tho.

 

Also it appears as though the exhaust gas control valve bypass mod has been done on the car.

 

Finally, is it possible to buy the different sized pills? 0.8mm, 1.5mm etc.

 

Thanks all