austinado16

Thought you guys would enjoy pictures of the damage cause by detonation, in the '93 Eurovan I'm working on. The heavily damaged piston is No.4 and the rest of the pistons look like the other piston I've shown. Looking down into the bores at the other pistons, the sides above the top ring were so erroded, you could actually see the top ring.
<img src="http://i187.photobucket.com/albums/x242/austinado16/P1040084.jpg">
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<img src="http://i187.photobucket.com/albums/x242/austinado16/ExhaustManifoldlowercrackemail.jpg">
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ricoblanco

Wow that's nasty.

4RingBling

89 Octane, which is mid-grade in the SE, works fine in my van causing no spark knock. I routinely get 20-22 mpg in mostly city/rural driving. First gear is only useful for pulling 18 wheel trucks out of the ditch or houseboats out of the lake, so most of the time I'm using only a four speed box (taking off from lights in either 2nd or 3rd gear if downhill).

I sure hope my exhaust manifold doesn't crack like yours did. Is yours also a two piece affair, with flex bellows between the two castings? I'd love to find one of the dual outlet manifolds and downpipes off the later 5 cylinder ACU code motors, as I could easily feel the difference this combo made in early A1 Rabbits and the van needs all the help it can get.

austinado16

I don't know the full history, other than that Carfax documented the mileage and showed that at some point after 88k it wouldn't pass smog and was labeled a gross polluter.

My hunch is that a shop did a timing belt, put it back together 1 tooth off, advancing both the cam and ignition timing, and then it just started eating itself.

I pulled another exhaust manifold off a '93 in the local yard and it was broken in the exact same spots (3 locations actually). I had it welded up after calling the dealer and finding out they were $640. I test drove an EV about a week ago, and it too had a broken manifold.

When you take these Audi 5 cylinder manifolds off and put a straight edge on them, that middle, No.4 runner is always about .010"+ gapped away from being level with the rest. It's that stress that breaks them.

Just got back from the machine shop. They're going to weld up the errosion and surface it for $240, and machine the exhaust manifold flat for another $40.

Orlando 4000S

Project is coming along fine though. should be another 2 weeks to finalize everything.

austinado16

Yep, been thinking of you and your engine daily.

Fair Cape-Cape Town

You should rather have sourced a branch manifold. I did this on the 5cyl 2.6 Vanagon. It made a dramatic difference to the torque and also improved gas mileage. Also better heat dissipation.

austinado16

It's not too late and there are a couple 5000's and 100/200's in the local yard.

The dealer wanted $650 for a new manifold.

DaveInSaltLake

glad to hear you're finally finding some good junkyards out there!

Fair Cape-Cape Town

Actually no Todd. The "Brospeed" stainless branch manifold is a custom made item. A company here made these in great numbers since most of the 5cyl Audis and Vanagons ended up with cracked manifolds.
I'm sure somebody in the states must have done the same. Theres something else for sale on E-bay. Not quite the same as what I have.<ul><li><a href="http://cgi.ebay.com/ebaymotors/Turbo-Exhaust-Manifold-5CYL-Audi-2.2L-S2-S4-RS2-K26-20V_W0QQitemZ200296825536QQcmdZViewItemQQimsxZ2009 0109?IMSfp=TL090109112006r13210">http://cgi.ebay.com/ebaymotors/Turbo-Exhaust-Manifold-5CYL-Audi-2.2