I understand at 87700 miles that the car isn't going to be like it was brand-new, but it's plain noisy and has a 'whine' to it. Also, it's very rough sounding, especially on cold starts. The 600s are known for being quiet and our '04 is sounding horrible. It's had both sets of ignition coils replaced, IC pump, ABC pump, hydraulic lines...pretty anything that could wear out has been replaced. Can't pinpoint the problem. I have it in the shop now because it has a hard time coming out of 'P'. Any ideas on the noisy engine?

 

i got a 600 and i had the same problem. coil packs and sparkplugs cured my issues. as far as I understand you have done these. Have you considered checking the ICM(ignition control module). this has been known to make the v12 run rough. Also as far as i kno small cracks and breaks in the the tubes underneith your engine cover can cause rough ride and loud issues. Go check out these and if not then get an oil change . Are you sure the coil packs were replaced with brand new ones w/ only bosch sparks. This really sounds like a coil pack/spark/ICM issue. Have you been taking care of this car? i know for a fact that v12's ar ethe worst cars to let sit and rot. they can deteriorate very quickly when not driven and slow when they are driven regularly. Continue to drive your car if it tends to sit around. She doesnt like that.

 

I got the car back from the shop last night. The car was leaning in the left side so the dealer replaced both the front and rear ABC level sensors @ $1600+ each, plus labor. I mentioned the growling/rough sound upon idle and acceleration, but the mechanics didn't notice anything This is the second dealership thst I have been to that cannot identify the problem.

The car is no longer quiet, and it sounds noisy upon acceleration. If anyone knows TT V12 600s, they are not supposed to make a sound ANY time. They examined he exhaust and found no leaks. I told them to inspect the engine mounts due to vibrating, but they said it was fine I just can't seem to find anyone that knows what they are doing in the St Louis area. Can anyone chime in? The car still gets great mileage on the highway, but I am thinking maybe one of the turbos has a defect?

FYI, the car is a daily driver, had everything replaced, including the coilpacks, pumps, etc. I would greatly appreciate any thoughts or opinions.

 

are you sure that they ran full diagnostics on it ? No misfire at all ...did the CEL ever come on ? was the ICM replaced ( Ignition control module ) ...what about the fuel pump and controller ? thats what I can come up with so far .. the M275 engine is finicky to say the least but there seem to be issues having to do with updated parts , ( Fuel pump . controller ) also from what I heard , there is also supposed to be an updated software or flash for the ECU .

 

check your cats. theyre under warranty.

 

I pulled it into the shop yesterday and had them run the VMI. Turns out only ONE of the ignition coil modules have been replaced. I'm having them look into an intermittent CEL and motor mounts that may be going bad. Noticeable vibration ~1500rpm. I wouldn't suspect the cats to be going bad, as I haven't heard a 'rattle can' under the car...yet.

 

Whine may be due to the ABC accumulator's, I gather.

 

The whine indeed was ABC-related. That was fixed during the last stint at the shop.

 

CEL was related to engine misfire in cylinder banks 7-12. This turned out to be in the RIGHT Ignition Control Module, the one that DIDN'T get replaced. The engine vibration was related to the hydraulic engine mounts being bad. They test drove the car, but couldn't re-trip the CEL. I'm still having them keep it until they fix everything.

Here's what's been replaced since the warranty expired:

Radiator cracked: $1000
Left ignition coil pack: $3000
Right ignition coil pack: $3000 <-- don't ask me why they didn't replace both at the same time

*alot of things got replaced under warranty, but still...*

ABC Pump replacement: $2500
Front ABC line leak: $1000
ABC Accumulators (front and rear): $4500

That's easily more than $10K in maintenance and I know that I'm forgetting other repairs. It's a great car, but this is the last V12TT I ever consider. Oh, and no more ABC or air suspension. That stuff tends to fail if you plan to keep your cars for more than 4 years.

 

That sucks, sorry to hear it. Yes, this is not the car to own without a very good warranty unless during the warranty period you replaced everything already.

You are kind of overpaying though...a coil pack should be $1500 or so to replace, not $3000. And if you are handy you can buy one for $875 or so and do it yourself.

Even my Benz dealer charges $1900 for an aBC pump, so $2500 for that seems high too. I'd start shopping around if I was you.

ABC struts are $599 each with lifetime warranty from www.arnottindustries.com, so that's another way to save huge money. Four of those from Arnott are $3000 installed, vs. $8K at a dealer.

Bruce

 

Accumulators should be $1k or $1.5k tops for both in parts, maybe $500 in labor. Even if you flush all the fluid and rodeo, which seems excessive, how did they cost that much? I think you need to find an indy mechanic.

 

i would love to find an indy mechanic, but in my part of the country, all they kniw is Fords, Chevys, V8s, and steaks. Anything more than a Toyota, Nissan, Kia, or Hyundai and they are bound to mess it up. closest indy is 130 miles away and I will consider them my my wifes Merc and my '01 W210.

 

Gotcha, that's unfortunate. Maybe tip the SA and ask him to help you out next time.

 

Just an update: I had them run a diagnostics and test drive and here's what the main technician said:

Multiple misfire codes on left bank cylinders
Error Code P20E7 - N92/1 (Right Ignition Coil Module)
Error Code P20F4 - N91 (ECI Ignition Main Unit)
Confirmed multiple misfires on cylinder #1 @ idle
Starting point would include: compression test and spark plug evaluation/replacement, right-hand ignition module, check ignition main unit, and left-hand ignition module before catalytic O2 sensor replace and re-evaluate.

I just repaired the front and rear valve blocks, so we're putting off the repairs for the time-being. At least the car doesn't sink now; it's been sitting in the garage for a week and no sagging whatsoever. The car runs perfect, but the CEL comes on and off occasionally. It didn't come on when they performed a 12 mile test drive loop, however.

I wanted to post this for anyone that has problems with their V12TT Mercedes, so that they may find this thread while searching.

 

Damn. And I was thinking that was going to be my next car.