Hi Guys,

Let me start with the back story. The car was working fine. I took it to the dealer to be serviced, and they recommended that I change the right engine mount since it was leaking, and the right outer CV boot since it was leaking axle grease. They quoted something ridiculous like $1200 to do both.

I said no thanks, bought the CV boot online, and two 034 density mounts since I figured I might as well change both. I took it to a neighbourhood mechanic who has always done good work for me in the past for a very reasonable price. He called and said one of the OEM mounts had a sensor, but I told him to still put in the 034 mounts since I figured the worss that would happen was that the car would throw an error code.

I got back the car, and it worked fine for a week. Parked it up one night, but in the morning it would not start at all. I hear the fuel pump, a slight whirring coming from the engine bay, and then a low level continuous beep lasting about 20 secs, also from the engine bay after I stop turning the key. I also hear a clicking sound coming from the starter.

I had someone give me a jump, but that didn't work. I thought it wasn't the battery, since it was replaced less than a year ago, but i tested it with a multimeter and it seems fine. All the lights, wipers, radio etc comes on fine. I also don't think it's the starter since the car has always started effortlessly, but I'm not absolutely certain.

Since the problem started so soon after the repair, I'm guessing the mechanic didn't replace something properly when he did the mounts, and there's maybe an electrical fault. I'm also wondering if the loose sensor wire from the original mount is flopping around, causing problems. I borrowed a friend's OBD scanner that I've used in the past, and there are no engine codes.

I'm far from a car-expert, so I'm hoping that one of you guys can point me in the right direction. Thanks for any input. The car is a 2006 A4, 2.0T

 

I wonder if the mechanic had to disconnect the starter and when re-connecting it didn't get the wires tight and they came loose. Outside of that not sure that loose sensor wire would short out to keep the car from cranking. What is the sensor in the motor mount for?

 

I'm sort of paraphrasing a good explanation of the motor mounts that I read online. Can't remember what site I read it from. The OEM mounts in some of the B7's are a solid hunk of rubber surrounded by a void with some type of oil, then more rubber. The sensors cause valves in the motor mounts to open and close according to how the car is handling while driving, which pushes the fluid to and from compartments in the mount, making the mount stiffer or softer according to the handling "requirements". So it dynamically adjusts the mount's stiffness which supposedly makes handling better. I hope I didn't butcher that explanation