Engine mount sensor fault

[paul_23]

Hi

Just had the RS6 engine out for a new torque converter and it is back in now but the following fault is recorded

17985 - Right Engine Mount Solenoid Valve (N145): Open Circuit
P1577 - 004 - No Signal/Communication

Anyone have experience of this - what is the problem and is it due to them crushing something or breaking something while fitting the engine?

Now the engine is back in what is involved to sort it out?

Thanks

[hahnmgh63]

I skimmed through ETKA and couldn't find a sensor on the mounting system but obviously there must be one there. I have my car on the lift in the shop and it is fairly hard to see the mounts even from the bottom but I'll take a look and post if I see anything obvious.

[vangelis]

YES, The engine mounting has a sensor and it seems they (or one of them) got broken while they fitting your engine. I have the same problem and I just bought 2 engine mountings from ebay for 100$ each.

[hahnmgh63]

I took a look at it on the lift and Vangelis is correct, both sides have a sensor which appears to be integral with the mount. They must have either forgotten to hook the sensor up after the install or broke off the plug portion that sticks out. It is easy to see with the plastic belly pan off the car. It is close to, and just below the base of the oil cooler or about 6"/15cm towards the inside of the car from the lower right side intercooler inlet. I think a good mechanic could install it without too much trouble by slightly lifting the engine and unbolting some oil lines and other pieces around it. Maybe you'll get luck and find that they just forgot to plug the connector after the install. The part # for the right side engine mount is 4B3199379D and costs about $200 here in the U.S. from the dealer. Sounds like Vangelis said, Ebay may be a good choice if they are OEM.

[paul_23]

Thanks.

The cheif mechanic is reviewing the problem and will judge if they do it at their cost or mine!

[vangelis]

The part # for the right side engine mount is 4B3199379D and costs about $200 here in the U.S. from the dealer. Sounds like Vangelis said, Ebay may be a good choice if they are OEM.

Hi, I need to get two engine mounts and I found it on eBay UK but I want to confirm first whether right and left side are the same and have the same part# 4B3199379D or not?

Thanks

[hahnmgh63]

My Etka says:

6 4B3199379C
hydro-mounting / F >> 4B-4-901 499* right / (6) 4B3199379D
hydro-mounting / F 4B-4-901 500>>

and:

3 4B3199379B
hydro-mounting left /

Not sure why the difference for the Right side. But when I put either right side # into the parts system it comes up with 4B3199379M and the left side comes up as 4B3199379J so both must have been superseded, at least in N. America.

[vangelis]

Thanks a lot hahnmgh63 for the info. but I'm confused now, is that means I can use in both sides part# 4B3199379D or not?

[hahnmgh63]

No, part# 4B3199379D is still only for the right side it just appears there may be a newer part out there. Maybe improved? Maybe not? Only Audi will know but they did supersede the part # with a new suffix. The one on my car is a "C" suffix so they must have changed it a couple of times over the years.

[vangelis]

No, part# 4B3199379D is still only for the right side it just appears there may be a newer part out there. Maybe improved? Maybe not? Only Audi will know but they did supersede the part # with a new suffix. The one on my car is a "C" suffix so they must have changed it a couple of times over the years.

Thanks, appreciate your help man. I will go to dealer morning and I will check with the parts dep. and update you here.

[RS6Steve]

I believe the mount sensors are an engine protection device. If you over torque the engine it effectivley twists in its mounts. The sensors detect this and back the engine off to preventing damage to it and associated components.

It will not affect your performance, just stop you breaking something if you have a heavy right foot :-)

[vangelis]

I believe the mount sensors are an engine protection device. If you over torque the engine it effectivley twists in its mounts. The sensors detect this and back the engine off to preventing damage to it and associated components.

It will not affect your performance, just stop you breaking something if you have a heavy right foot :-)

I agree with you, anf I have a heavy right foot ,that is why I wanna get it fixed soon.

[kevinyoung03]

Thanks for helping me here. I was looking for the solution of this problem.

[vangelis]

Well, I just confirmed with the dealer, the part# 4B3199379D for right side has been superseded by part# 4B3199379M.

[Shoppinit]

It will not affect your performance, just stop you breaking something if you have a heavy right foot :-)

If the engine mount sensor is causing a defect code then the ECU will dial back turbo pressure to reduce power and reduce further damage. The engine mountings are quite a common failure on the RS6.

[uncfrk]

Pure M.S. has mounts http://www.purems.com/products/products.php/CA=1484 I don't know anything about Pure Motor Sports, but the allroad guys use them.

[V8weight]

Pure M.S. has mounts http://www.purems.com/products/products.php/CA=1484 I don't know anything about Pure Motor Sports, but the allroad guys use them.

I like the look of those mounts, but you would have to install a resistor in place of the original motor mount solenoid to fool the ecu into thinking they are still there. For what it's worth, I've had good luck with Pure Motorsports. I've been considering doing both the Sterns motor and transmission mounts in my car. They will cause noticeable vibration over the stock mounts, but should offer better feeling shifts.

[vangelis]

If the engine mount sensor is causing a defect code then the ECU will dial back turbo pressure to reduce power and reduce further damage. The engine mountings are quite a common failure on the RS6.

R u sure about that Shoppinit? Faulty mounting can cause a loose in power???