I recently purchased my second mercedes (I had owned a 1989 300SE and loved every minute), a 1998 E320. When I purchased it, it had 57000mi on it, and the previous owner took immaculate care of this car. But at 62000mi, It started to make rattling sounds underneath the car. I took it to a local shop to see if they could tell me what the noise was. I was informed that it was one or both of my cat. converters. Man, I was not happy...failing at 62000mi!!!!!! I never had a problem with my 300SE. which unforunately I lost that car in an accident ( i walked away with airbag burns, but the other people went by care-flight and ambulance!!). But anyways.. So now I have to replace the cats..what my real problems are:

1. Can't get the key to turn (changed batteries in key already and tried second key too)
2. Car seems to be stuck in park.
3. When I could get key to turn before, auto start was labored for a few seconds (kept cranking until it finally started).

When I insert the key, I can hear the steering column unlock...and you can turn the wheel just fine..but can't get shifter to the neutral position. Also, I can remove the key with or without my foot on the brake pedal..which i don't think is normal and a sign of the problem. My thinking is this...I need to concentrate my troublshooting efforts somewhere in the brake pedal circuit...am I going in the right direction?

now as far as the starting problem, could that be a result of faulty cat. converters? I'm prepared to undertake a sparkplug change out (it's due anyways). But is that going to help solve my starting problem. Or, is it something that I need to dig into a little deeper...I'm trying to stick to the KISS method here.

Feel free to respond in a technical sense. I'm am no stranger to it...I am an aircraft maintenance technician by trade.. but sometimes find today's cars baffling....

D

 

KISS?
Your symptoms do not seem to link together.
Can't shift out of Park. Likely cause....No ignition and/or brake light signal.(Safety feature). Lack of brake signal is the brake switch.
Laboured start...Hmm...possibly fuel.
You say key won't turn so how did you get the car to crank? Seems like the Key or EIS (Electronic Ignition switch) is faulty but this can't have anything to do with the cat change.
The EIS/Key could easily cause the Park selector problem.

Rattling cat is unlikely to effect starting if noise is reasonably recent. i.e. no blockage. Cats are very expensive. Very common problem due to loss of packing material holding brick. Been trying to persuade MB that this is a design issue for a year now but no luck so far. I have the necessary pics to demonstrate the problem precisely showing the propogation of the problem on one cat BEFORE the situation deteriorates to something which could have been caused by any number of causes.
Since I don't want to spend £1000 per car approx (both my cars had the problem) to replace the rattling cats I have removed the brick from the gearbox cats....No rattle now and passes UK emmissions test by a mile! You can't even see (unless you look with a very critical eye) where the can has been opened.
If you want pics PM me with your email.

 

KISS=
Keep
It
Simple
Stupid

When I could get the key to turn...I can't get it to turn anymore. Goes in..you can here the steering column unlock...you try to turn it...and it won't turn but a tiny bit. if you hold the key the tiny bit that it will move and hold it...you hear a couple of clicks then nothing at all.

While tinkering with the key problem, I noticed that the shifter wouldn't move out of park maybe cause I can't get the key to turn at all???

I will PM for the pics...is there a lot of intense work to remove the material that's rattling in the cats?

I bought some new cats already...well one..( ordering fiasco..and ended up getting only one) Are they hard to replace...looks like just a couple of exhaust manifold bolts...and a few hangers...

Do you know how much the EIS modules cost...in american dollars.. =) and also the brake switch??

I look forward to your next post...

D

 

EIS problem.

 

EIS problem.

 

Thanks for KISS.
To change the cats is easy / straight forward.
Best to replace than cut open however its the cost thats the problem. I assume you are using OE parts. The MB ones are an MB special shape. If not you may encounter problems in the limited space.
Will send the pics. Hope you have a good size mail box.
Looks like you will also have to pay for the EIS.
Stuart