Problem to watch out for

4.2 V8 40v biturbo - 450 bhp
4.2 V8 40v biturbo - 480 bhp (plus)
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topher57yellow
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Problem to watch out for

Post by topher57yellow » Tue May 05, 2015 7:49 pm

Hello
Lost engine power and electrics driving home at the weekend. Luckily there was a lay-by close by and managed to coast safely.

Very thorough RAC mechanic traced the problem to a connection and fuse under the header tank. Took a while, had to take out the lower dashboard in both footwells in order to trace the power. Common fault apparently as the drainage holes just below the header tank get blocked and the connections above rust away.

I reckon the best way to avoid this is to periodically remove the header tank, clear the area of debris and liberally squirt some WD-40 in there.

This has probably come up in a previous thread but it's something to look out for.

p19dro
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Re: Problem to watch out for

Post by p19dro » Tue May 05, 2015 10:36 pm

Coolant header tank?
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Mɐʇʇ
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Re: Problem to watch out for

Post by Mɐʇʇ » Tue May 05, 2015 10:56 pm

Yeh, there's a pair of really heavy amperage fuses behind it.
"not a professional engineer, mechanic and mechanist"

bam_bam
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Re: Problem to watch out for

Post by bam_bam » Wed May 06, 2015 10:44 am

Yep, I've endured this issue. Audi stealer diagnosed a failed earth strap, quoted £1300+ to fix. I decided to say 'fcuk you' and I had a new alternator put in by my local indy at a fraction of the cost. The issue remained so I called in a very good auto sparky, he traced the problem to the fuse (250A?) under the scuttle. Sorted and still at a fraction of the cost of the stealer... without replacing the earth strap.
No matter where you go, there you are.

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lswing
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Re: Problem to watch out for

Post by lswing » Thu May 07, 2015 3:52 pm

Dealt with the same thing, good for everyone to take a look in there.
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