hi i have a 02 audi a4 3.0L manual with a recent timing belt failure. when i brought the car to the shop, the tech said the leak down test showed two cylinders were good while the 3rd one was not. i decided not to go ahead on a 6k bill and ask around first. i have a a couple of questions. first, the car died after i parked it and would not restart so i figure the damage was not that extensive, would i be able to just replace cylinder heads and do a timing belt or would a whole engine need to be replaced? also about replacing an engine, does it matter what transmission you have. does the ecu need to be reprogrammed? what goes into an engine swap besides obviously connecting all the harnesses?
That's a bummer to hear about a timing-belt failure; this type of event is the reason most Audi owners are pretty cautious about monitoring the time/mileage that their timing-belts are in-service (3.0L V6's timing-belts are usually changed at 75K-mile/7-year intervals). Please be aware that the Audi engines are all "interference" designs, so under normal operating conditions, the valves and pistons alternately occupy the same space within the cylinders. A timing-belt failure means that lots of expensive parts will catastrophically meet one another at high velocities. I'm unaware of any means of beginning to accurately assess the carnage short of pulling both heads from the 3.0L V6 engine. In addition to the valve-train and the pistons, you'll need to determine if the cylinders have sustained any damage.
Depending upon the extent of the damage, you may need to look into procuring either a short-block or a long-block replacement engine. The "short block" includes the engine block, pistons, rings, pins, connecting rods, crankshaft and main/rod bearings. The "long block" adds the cylinder heads and all of the attendant valvetrain components (valves, camshafts, variable-cam sub-systems, etc.). A quick Google search turned-up a couple of Audi engine rebuild specialists with available stock of B6-platform A4 3.0L V6's at ~$3500 for a short-block and $5500 for a long-block replacement engine (of course, shipping costs will add to the bottom-line....).
I wish you good luck in restoring your Audi to operational status!
You may be able to rebuild just one cylinder head if you are trying to keep cost down. The valves may have mashed into the piston and also damaged them. Is this a dealer ? or a Indy shop that you trust? I would get a second opinion and post this in the general forum that relates to your year and model as well as the sites I listed below. If the 2nd opinion is the same you could probably buy a used engine off Ebay,Craigslist,junkyard or search the classifieds in audizine.com quattroworld.com this site as well.You will save thousands compared to that 6,000 figure you gave.Good luck
A timing-belt failure is a very serious matter in an Audi. All Audi engines are "interference" designs, a design approach in which the valves and the pistons alternately occupy the same space within the cylinders. The timing-belt is the sole means of maintaining the synchronized movement of these engine parts; a timing-belt failure means that many expensive parts have collided with one another in a very catastrophic and destructive manner. This situation is the reason that Audi owners tend to be incredibly ****-retentive with regards to knowing with absolute certainty that their car has had a reasonbly recent timing-belt service.
The only means of accurately assessing the damage/carnage caused by a timing-belt failure on a 3.0L V6 is to pull both heads and eye-ball the situation first-hand. If the damage is limited to destruction within the heads along with damage to the tops of the pistons, the engine block may be OK. However, if the cylinder walls have been compromised, you'd be facing the need to procure a "long block" (a "short block" along with all of the cylinder-head hardware). A quick Google-search shows that a number of Audi engine-rebuild specialists have A4 3.0L V6 "short blocks available for about $3500 and "long blocks" for about $5500; of course, the labor to swap the engines and the shipping costs would be in addition to the cost of the rebuilt engine.