The dealer told me the ECM needs to be replaced ($1300 there plus the intall and program for $168). The part number is 4D0997551EX. I have been looking for HOURS and can't find it anywhere, anyone have any advice?
The car is a 1999 A6 2.8L Quattro.

 

that's nuts. unless i'm assuming more knowledge than i have on the matter, he's referring to the computer that manages the engine. alot of people call the same part different things. PCM, ECM, ECU, Computer, Computer Control Module, the list goes on. the reason being is different companies call them different things. for instance the ECU in my Audi is the PCM in my Grand Prix. $1300 is a joke. call your local scrap yards, but that's hoping to get lucky with an import. Ebay will have a selection. or you could buy a performance ECU from APR or GIAC. there are others but those are the most common.

 

here's a link. none are the exact part number, but it will give you an idea of the cost of a used ECU for a 98 A6

http://www.autopartsfair.com/audi-us..._computer.html

 

For used try www.shokan.com with the part number. I would imagine you would still have to have them tweak it to your car.

 

Shokan has a warranty on their parts, while most salvage yard do not.
To install yourself you would need VAG-COM from www.ross-tech and the BentleyPublishers.com Audi shop manual. However, if the ECM comes from the exactly same Audi year, model, engine, FWD or AWD and transmission it should then be a direct match. Even if the ECM has the same part number, the coding may need to be changed if it came from a differently configured Audi.
What is wrong with the ECM? Sometimes it is a problem with the wiring between the ECM and the sensors. Hence, you could test the wiring between the the ECM and the sensor with the ECM removed per the Bentley instructions.

 

Ebay Germany.. 200 EUR

http://stores.shop.ebay.de/VW-Teile-...&submit=Finden

From what I found, the original part # for that was 4D0907551AH... which is on ebay http://cgi.ebay.com/ebaymotors/Audi-...#ht_1538wt_923



AUDI A4 00-01 Elec Cont Unit (ECU); 2.8L, eng ID AHA
AUDI A4 02 Elec Cont Unit (ECU); VIN model "D" (8th digit), 2.8L, eng ID AHA
AUDI A4 97 Elec Cont Unit (ECU); 2.8L, eng ID AHA, ID 4D0907551AH
AUDI A4 98 Elec Cont Unit (ECU); 2.8L (eng ID AHA), ID 4D0907551AH
AUDI A4 99 Elec Cont Unit (ECU); 2.8L
AUDI A6 00 Elec Cont Unit (ECU); 2.8L, AT, eng ID AHA
AUDI A6 01 Elec Cont Unit (ECU); 2.8L, eng ID AHA
AUDI A6 98 Elec Cont Unit (ECU); VIN model "B" (8th digit), (left cowl)
AUDI A6 99 Elec Cont Unit (ECU); (left cowl), eng ID AHA
PASSAT 98 Elec Cont Unit (ECU); 6 cyl
PASSAT 99-00 Elec Cont Unit (ECU); 2.8L (V6), eng ID AHA

Ident: 4D0907551AH
Ident: 4D0907551AP
Ident: 4D0907551H
Ident: 4D0997551EX


Double check that though, it might need a software upgrade.

 

Thank you all for your help. I was on a wild goose chase....here's what happened yesterday.

After getting on the shokan website I sent a request for them to check for the part number I had which they send a reply to later. Also saw the foreign ebay listing but didnt know any way to get that. After looking around some more I decided to call the dealership and ask them for the part number for the '99 Audi A6 ECM because I "lost" it. The guy caught on that I had it diagnosed there and said "let me pull your invoice, the part number should be on there and I'll give you a call back". Bummer, I was about to get the same part number I already had. He called back and gave it to me, but said "I'll also give you the stock number..." SUPER! After getting that which was (Ident: 4D0907551AP which IS possible to find on ebay and such) I checked my email and shokan wrote back saying the part number I gave them was unavailable because it was a rebuilt item and asked for the stock part number......all the frustration one website can solve!

I ordered the part yesterday and it comes with a 30 money back guarantee....and it was $130 shipped instead of $1300 at the dealer.

Thank you so much for all the advice!

 

Uhhhh, maybe a dumb question, but if your car already has a "rebuilt" ECM and now you need another one, doesn't that sort of point to another problem?

Good luck,

Bob

 

I'm not aware of anything in the car that could make the ECM go bad. From what I've seen on the forum its not to uncommon and some even keep a spare for if it happens. Does anyone know if there's a cause making ECM's expire?

 

you can simply visit the sites and look for the ECM