Next up in this never ending story is the exhaust, its old, rusty and something inside the cats rattles there's 2 codes for catalyst system below efficiency:
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This basically means the car needs all 4 new cats and oxygen sensors as they're all 21 years old at this point and wont come out in one piece.
Example of what i mean by rusty exhaust:
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Flex joints were torn too, but i didn't get any pics.
Video of the startup rattle:
I decided to go with BM Catalysts pattern parts as OEM Audi parts would cost around £4k going with BM parts it all came to around £557 for every part including exhaust paste and bandaids.
So, the new cats came and they were of an average quality so i had to de-burr parts of them:
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After de-burring all the cats i removed all the stickers from them and sanded them down for painting with a high temperature exhaust paint, this was an absolute waste of time as all the paint came off anyway and smoked and smelled really bad after fitting/first engine start:
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Old vs. New
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The whole replacement procedure took 2 people (me as a helper) and about 9 hours. The hardest and most crucial point of it was removing the nuts at the exhaust manifolds. If any of the studs snapped, it would mean and engine out job.
5 out of 6 came out ok, but the last one (as it always is) put up a fight. The solution turned out to be carefully dremeling off the nut so it can be undone:
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Its position in the engine bay also wasn't helping but it was still the easiest one (top one) to get out. If it was any of the other 2 it would have had to be done from underneath:
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As i later found out, the rattle from the exhaust was caused by one of the lambda sensors breaking off inside the cat.
The end result was this:
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Next were the front calipers.
They are rusty and ugly, brakes are weak and the bleeders are seized so brakes can't be bled properly.
Before:
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During disassembly:
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After:
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Bleeding:
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Fitted on the car:
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Moving on, rear driver side speaker grille was broken, so i replaced it with a spare:
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Hand brake trim clip was broken:
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So i designed and printed a repair piece:
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Fitted:
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Another annoying issue with the car was a faulty PDC sensor in the front bumper so, bumper off:
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Crash bar taken out of the bumper to reveal the parking sensors:
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New sensors going in:
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Order of spare parts from audi tradition including new pdc sensor brackets as they like to brake off:
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I also replaced the 2 seals for the headlight washer, as the pump was dead and the seals were leaking:
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Last annoying fault was a chattering INA tensioner replaced less than 2000 miles ago:
I replaced it with another one:
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And it seems happy now:
Oil level sensor was also replaced for a Hella one which had the Audi logo grinded off during production ;)
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Part 10 will cover various OEM+ upgrades:
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