Bora 2.ol running probs/low mpg

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Tue 21 Jun 2005 18:23
Bora 2.ol running probs/low mpg - bora
Hi all

Hope someone can help. I have a 1999 2.0l petrol Bora. Recently the car was sluggish and did't want to rev. I changed the air mass meter and it was spot on for a few weeks. Then the mpg went from 40 down to 25-30 and the exhaust smelled of unburned fuel. Next I checked the output voltage of the Lambda probes, mine has two, one on the exhaust manifold and one on the Cat. I recorded 0.010v cold and they both climbed to 0.023v when the coolant indicated 90 c(normal). The Lambda probes were fitted but the electrical plugs were disconnected when I tested them. Next I spoke to VW and they said the problem is usually the air mass meter or the coolant temp sensor. I changed the temp sensor and there was no change. The car was due an M.O.T. and it failed on emmissions, M.O.T. guys suggested a local mechanic who put it on his diagnostic for a tenner, nice bloke, and it showed faults with the Lambda probes, air mass meter and coolant sensor, no suprise since I'd been dicking around with them. He cleared the faults and the car ran a treat once more, mpg back to normal and no smell of fuel. 200 miles later and the mixture is cocked again and mpg through the floor. Changed air filter and spark plugs today, have fuel filter and H.T. leads to change tomorrow, the car hasn't been back on the diagnostic yet.

Any help would be most appreciated.

Paul
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Wed 22 Jun 2005 12:07
Bora 2.ol running probs/low mpg - borasport20
I had the same symptoms with mine - local VW dealer proved incapable of identifying or fixing the problem, and I just got rid as soon as it was out of warranty.

Have you checked the HT leads ? They are a bit difficult to get at, but if you fancy changing them, I can strongly recommend getting a set from Magnecor - www.magnecor.co.uk/ When I was dealing with them they had never made a set for a bora, but the guy I was speaking to, Phil de Witt, was very helpful - I now find out from their web site, he's actually the MD !


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Wed 22 Jun 2005 12:57
Bora 2.ol running probs/low mpg - Aprilia
Sounds like fuelling rather than ignition.

Could by an exhaust gas sensor, or could be a number of other things including the new MAF gone faulty or a wiring problem.

For £10 I would get it back on the diagnostic tester.
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Wed 22 Jun 2005 13:59
Bora 2.ol running probs/low mpg - borasport20
p.s. - if you have access to a laptop, why not see if you can get hold of a copy of VAG-COM and do your own diagnostics ?

I wouldn't want to impugn your local mechanic, but when I was having issues (2 years ago) the local dealerships were charging £35 and £60 for diagnostic checks !


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