B6 3.0 crank no start, thinks is a manual, but fixed when ground ECU to battery

[bbgirlbrie24]

I hope this is where I post this, this is my first post. But here goes.... I have a 2006 A4 cabriolet 3.0 quattro (BNG engine) that i just swapped the transmission on. We took the engine out because it was badly mistreated by prior owner and wanted to clean her up and get a good look. Changed the valve cover gasket, fixed the oil pan gasket, cleaned her up and put her back in. NO START. Fuel pressure fine, power directly to fuel pump starts and runs amazing! Ground the ecu to the battery. Starts fine, take off the ground? Crank no start. Did we miss a ground somewhere?.... Then it rained and the cover was off my ECU box. Water go in it. I blew it out with air compressor removing all the relays and dried it out completely. Waited a couple hours and plugged everything back in and went to start and got the message "Press clutch to start engine" WTF???!!!! Half way through the night my engine decided to change to a manual!?!? Put the ground back on the ecu message goes away, starts right up. I am also getting a LOOOOONG beep on start-up followed by a few short beeps, then a pause then it starts over. I have NO IDEA what to do now. While this is all going on I have also had to replace the BCM and CCM due to water damage from leaks so the convertible top and windows would open and close, replaced the spark plugs, oil filter, breaks and rotors. I have no check engine lights but I do have an ABS, traction control light on dash as well as a constant check message for fuel even though it reads at half a tank, oil pressure but the pressure is fine and a few other little ones like wiper flued and tail light. My husband and I own an auto repair shop and have maxisys ultra. We specialize in BMW's and thought this German engineered would be an easy add to our personal collection, boy was I wrong.....any help on where to start or what to look at or what is wrong would be tremendous! Thank you in advance. Oh and if anyone has the pin out for the ECU I'd be forever grateful!!

[RLee556]

I hope this is where I post this, this is my first post. But here goes.... I have a 2006 A4 cabriolet 3.0 quattro (BNG engine) that i just swapped the transmission on. We took the engine out because it was badly mistreated by prior owner and wanted to clean her up and get a good look. Changed the valve cover gasket, fixed the oil pan gasket, cleaned her up and put her back in. NO START. Fuel pressure fine, power directly to fuel pump starts and runs amazing! Ground the ecu to the battery. Starts fine, take off the ground? Crank no start. Did we miss a ground somewhere?.... Then it rained and the cover was off my ECU box. Water go in it. I blew it out with air compressor removing all the relays and dried it out completely. Waited a couple hours and plugged everything back in and went to start and got the message "Press clutch to start engine" WTF???!!!! Half way through the night my engine decided to change to a manual!?!? Put the ground back on the ecu message goes away, starts right up. I am also getting a LOOOOONG beep on start-up followed by a few short beeps, then a pause then it starts over. I have NO IDEA what to do now. While this is all going on I have also had to replace the BCM and CCM due to water damage from leaks so the convertible top and windows would open and close, replaced the spark plugs, oil filter, breaks and rotors. I have no check engine lights but I do have an ABS, traction control light on dash as well as a constant check message for fuel even though it reads at half a tank, oil pressure but the pressure is fine and a few other little ones like wiper flued and tail light. My husband and I own an auto repair shop and have maxisys ultra. We specialize in BMW's and thought this German engineered would be an easy add to our personal collection, boy was I wrong.....any help on where to start or what to look at or what is wrong would be tremendous! Thank you in advance. Oh and if anyone has the pin out for the ECU I'd be forever grateful!!

Audi's are somewhat notorious about being finicky about grounding. Find every single ground you can, especially in the engine bay, and throughly clean it.
That's where I'd start.

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