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There is a small black box with a vacc hose running into it (located in the engine bay, just in front of the driver side of the firewall) - follow this hose and make sure its connected - if there is nothing wrong with your turbo, this will be the problem.

As Stan said, it's the black box by your brake master cylinder, it's called the Pressure Sender Unit. They'll die after a while, but you can usually source them from wreckers pretty cheaply. Simple swap one bolt.

hi all,

thanks all for the replys and help. Yesterday night i took it for a spin to give it another go. after 10 mins of nothing it just decided to wake up. At first the needle was jumping around a bit until it settled down and started measuring properly. Then this morning when I started, it was working fine, then it died again for about 10 mins, then it came back. Fine since.

It seems that it wakes up when i start to hit the turbo. Usually i drive granny style to conserve fuel on the weekdays. like you guys said it could be the pressure sender unit. anything else it could be? also should mention ive only had the car for about 3 weeks, just imported.

hi all,

thanks all for the replys and help. Yesterday night i took it for a spin to give it another go. after 10 mins of nothing it just decided to wake up. At first the needle was jumping around a bit until it settled down and started measuring properly. Then this morning when I started, it was working fine, then it died again for about 10 mins, then it came back. Fine since.

It seems that it wakes up when i start to hit the turbo. Usually i drive granny style to conserve fuel on the weekdays. like you guys said it could be the pressure sender unit. anything else it could be? also should mention ive only had the car for about 3 weeks, just imported.

About 99% sure it's your sender unit. Exactly the symptoms of a sender unit on it's way out.

yeah just a faulty sender unit.. guage is fine.. and yeah not a priority as it only shows you the boost level.. how much do you look at it? especially if you drive like a granny..

Can i thread Hi-jack alone the line? You know the hose that connects to the pressure thingy, mine keeps cracking and coming off and making a hissing noise in the engine bay (which also causes the turbo gauge to not work, so im still on topic :D) but, i cut the hose at the cracked area and stuck it back in, but the problem is im running out of hose to cut, and i think i need to replace the new hose...has anyone done this? and is it hard?

Piece of piss mate. Just unplug the hose from the sender unit to the plenum... measure it up and buy a new one. Then plug back in. While you're there, try locking it in place with cable ties so it doesn't work loose.

Piece of piss mate. Just unplug the hose from the sender unit to the plenum... measure it up and buy a new one. Then plug back in. While you're there, try locking it in place with cable ties so it doesn't work loose.

Cheers Howie, always helpful. :D I was just worried coz when i looked at it at night it seemed a bit niggly. lol

I believe from memory it's a special hose - 2mm ID going into the port in the plenum and 4mm at the sender. You'll be hard pressed to find such a hose so you can either 1) find a step-up/down adaptor (plastic one will do) or 2) use a 4mm hose and just wrap a small zip tie around the inlet port to hold it down.

i have this same problem in my basically stock 34, the boost gauge just decides to die and then come back to life a few mins later every once in a while, i started a thread on it also, and i think it might have been howie that said the same thing to me, that it would be the sender unit, im yet to source and install a new one though seeing as it doesn't seem to be causing any problems

yeah, exact same. dies then 5 mins later, strungles and comes back. i'll get to fixing the pressure sender one day i guess. car still flies nicely so im still happy.thanks for all the help all. one last question is what exactly does the boost sender unit look like? i can't seem to locate it. i know i'ts near the brake booster, but still can't find it.

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