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Boost Issues - BPU but NOT boosting above 0.76 bar


Sheefa
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OK guys,

 

See this thread for a bit of info: http://www.mkivsupra.net/vbb/showthread.php?t=100599

 

I have the Blitz SBC-ID I model installed and this was fitted by Phoenix in Watford, who I assume, are pretty good, in May 2006.:innocent:

 

However, despite raising the Set and Gain functions, and making sure each Channel is on Mnaual NOT Auto mode, I still can't get above 0.76 bar!! The video attached is working on Channel 4 which has a SET of 60 and a GAIN of 25. As you can see, it's going nowhere and I was doing over 6 at the time it hit 74, past 4,000rpm too.:( http://www.youtube.com/watch?v=xkdbiCt0vwc - watch from the 55 second mark! :)

 

For info, my settings are as follows (again all in Manual mode):

 

  1. Channel 1: SET 20 GAIN 10
  2. Channel 2: SET 25 GAIN 10
  3. Channel 3: SET 35 GAIN 15
  4. Channel 4: SET 60 GAIN 25

 

Does anyone have a clue what could be wrong? I'm worried I might not be BPU after all! :( Surely, with a full decat, BC, better fuel pump and hybrids I should be seeing well above the 1bar mark?? :search: I don't want to up the set/gain further just in case I do something adverse to the engine!

 

Help guys! No idea what to check.:(

 

Thanks,

 

Greg

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Mark,

 

Haven't asked Chris yet as only found this out for sure today. He checked the fuelling of my car etc using his Motec and all seemed fine, but don't know about boost. I did mention that to my recollection I've never seen over 0.8 (0.76 to be precise) bar before. :(

 

It's a S/H unit guys, fitted by Phoneix only in May 206 - so new when purchased then!!

 

Haven't checked for any leaks Terrible, the car is running very smoothly and only just had it back from CWs. New FMIC, new turbo soelnoids, rad etc.

 

I haven''t done a run with the BC off yet though. Will it show the boost level still then? I could also confirm using the mechanial boost gauge.

 

That's a point. There's a mechanical boost gauge (a Greddy one) in my Glovebox which I've disconnected the bosing from, would this affect my Boosting as I thought it was just another feed to a gauge?

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You must either plug the hose or refit the gauge to the hose. With no cats and an aftermarket exhaust you should be seeing around 1.0 to 1.2 bar boost without any boost controller fitted. If I were to look at it the first thing I would do is remove the boost controller hosing and return it to stock hosing. I was seeing about 1.0 to 1.1 bar and the fuelling was fine. I suspect a hose is off, split or something. I can have a look at it after the end of next week, if nothing is obvious.

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Thanks Mark. The boost gauge is a mechanical one mate and I never really look at it as it's tucked into the Glove compartment and I rely on the BC - stupidly!

 

Cheer Chris for the response. Appreciate it. I'll refit the hose to the mechnical boost gauge tomorrow and take her on an early morning run to see if that sorts it.

 

I thought I should certainly see more and I remember you saying everything looked good, hence thought this was a tad odd! Might need a trip down again then, hopefully not (no offence intended!) but if so, I'll give you a shout tomorrow. As Pete mentuioned, I'll be at Donington on Tuesday anyway, so perhaps if you do have a mo to check it out then, that would be great. All the experts in one place hey, fantastic, free labour too! ;)

 

Cheers Chris.

 

Greg

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DAMN. I did have the Mechanical Boost Gauge hooked up, must of reattached the other night. Vaccum hose is on nice and tight, can't see any splits in the immediate vacinity.

 

Also, it too reflects 0.76 bar or less as per my BC reading. :(

 

Video is here: Apologies for the loud Glaxy music! On 0.74bar I was hitting 70mph over the 5,000rpm range too. Skip forward to the 50 second mark.

 

http://www.youtube.com/watch?v=xkdbiCt0vwc

 

My car is gay.

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If the boost controller solenoid isn't opening it will hold boost at wastegate level, which isn't enough to bring 2nd turbo on line. As I said before, remove the BC plunbing and put it all back to stock.

 

Thanks Chris. However, I can 'feel' tubbie number 2 come online when I put my put down for sure - I think! I still get a whack.:search:

 

Sadly Chris, removing all BC plumbing and returning it to stock is not something I would be even mildy capable of doing, or even having a partial knowledge of where to start. I know, I suck! :innocent:

 

Greg :(

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If i get a minute I'll have a quick look tomorrow, but I won't mess too much as you will want to get home in it, no doubt :)

 

If you can Chris, that'd be very much appreciated. Only if you have the time of course as I know the track day lasts.....well all day!

 

It's not actually causing any 'problems', and she's running smoothly, but would be great to have this sorted! Thanks mate. :)

 

Greg

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