Turbo not turboing: Kudos for best/fastest answer

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davekmoore
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Turbo not turboing: Kudos for best/fastest answer

Postby davekmoore » Sun Aug 24, 2014 11:01 pm

Halfway through a lap today the turbo stopped boosting. The boost gauge read zero. No plus or minus figures. No overheating so it wasn't the ECU saying no more fun. No mechanical noises or signs of anything wrong mechanically apart from the valvegear noise still present 5,000kms after the rebuild. The car drove 3 hours home sort of okish with the turbo audibly spooling up. At the same time the cruise control has either stopped working or only works randomly.

Thoughts?
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bartmanftw
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Re: Turbo not turboing: Kudos for best/fastest answer

Postby bartmanftw » Sun Aug 24, 2014 11:09 pm

Sounds like a vacuum leak.

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Tezzax5
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Re: Turbo not turboing: Kudos for best/fastest answer

Postby Tezzax5 » Sun Aug 24, 2014 11:17 pm

Wastegate actuator not shutting properly ?

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hks_kansei
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Re: Turbo not turboing: Kudos for best/fastest answer

Postby hks_kansei » Sun Aug 24, 2014 11:32 pm

Boost gauge hose has come off?


If down on power, intercooler pipe come off, or split, leaking air under boost.
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Re: Turbo not turboing: Kudos for best/fastest answer

Postby zossy1 » Sun Aug 24, 2014 11:49 pm

Is it boosting or isn't it? Have you lost half your power, or just getting a zero reading on the gauge with normal power levels?

If so, my money is on an intake-side plumbing leak, like a blown intercooler pipe or something.

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Re: Turbo not turboing: Kudos for best/fastest answer

Postby greenltd » Mon Aug 25, 2014 5:34 am

May sound silly, Fuse? Otherwise look where the cruise control connects to the throttle just in case the two issues are related.

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Re: Turbo not turboing: Kudos for best/fastest answer

Postby pezchops » Mon Aug 25, 2014 6:05 am

as cruise uses vac and that is playing up you have a vac leak.
i recently had similar on my turboed car .
i lost boost but car still ran ok and i checked under the bonnet and all looked ok.
i continued my trip but it started running worse and worse until it wouldn't idle.
further look under the bonnet found a hose completely off its connector.
the first symptoms (like yours)where from the hose just being loose and near off but when the hose eventually coming right off it wouldnt run.
i would check all of your hoses while the motor is running...wiggle joins and push on pipes here and there trying to get an idle response.
it can be hard to track down a leak.
some guys recommend spraying carby cleaner over your hoses and your idle will rise at your leak but i cannot say ive done that...that stuff is flammable.

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davekmoore
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Re: Turbo not turboing: Kudos for best/fastest answer

Postby davekmoore » Tue Aug 26, 2014 6:30 pm

Reckon pezchops is the winner. Thanks also for all the other suggestions.

There was no boost on the gauge because the pipe to the gauge was off.

There were also at least two pipes on the intake side almost off and one completely off. Putting all of them back on restored the boost and the reading on the boost gauge. You can imagine my relief after the journey we've been through this last 18 months that it was this simple a fix.

Needless to say, all these pipes are now properly secured instead of just being pushed onto a couple of plastic barbs. Having discovered this I took a further look around the engine bay and found several other fixings that needed tightening, or even renewing in one case, as the nut and bolt had gone missing. Disappointing this.

Anyway, I'm not disappointed that Winton finished early because of my concern about the lack of boost, because I think I'd pretty much tired myself out by then anyway, especially taking into account the three hour drive home.
UK since return: Standard NC2 (horrid), C200K, ND2 BBR, NC2 BBR200 (loved it), NC BBR300 (better than BARMY), V-Special, turbo NB8B (my 84th car)

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Re: Turbo not turboing: Kudos for best/fastest answer

Postby pezchops » Tue Aug 26, 2014 6:51 pm

bartman and HKS where first on the leak idea ..i just rambled on more

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Re: Turbo not turboing: Kudos for best/fastest answer

Postby speed » Tue Aug 26, 2014 6:51 pm

Awesome news! :)


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Re: Turbo not turboing: Kudos for best/fastest answer

Postby speed » Tue Aug 26, 2014 6:52 pm

pezchops wrote:bartman and HKS where first on the leak idea ..i just rambled on more

But it's how you rambled :)


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Re: Turbo not turboing: Kudos for best/fastest answer

Postby 93_Clubman » Wed Aug 27, 2014 10:35 am

davekmoore wrote:You can imagine my relief after the journey we've been through this last 18 months that it was this simple a fix.

Dave, relieved to hear this was a simple fix.


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