1994 E320 Wagon engine wiring harness
I am new to MBworld, new to Mercedes-Benz ownership.
I have just purchased my first M-B product, a used 1994 E320 Wagon in really clean shape.
It was traded in at the VW-BMW dealership where I work.
I love the car, and recently took it in to European Motorsports here in Kansas City to have a checkup.
Here is what they found, and I would like input from those of you in the know on the E320s, on what I should have done, how critical things are, etc. I am trying to maintain the car without spending my life savings, so I am trying to sort out what NEEDS to be done soon and what can wait.
1. I am told that a lot of the engine wiring harness insulation is brittle, and is pulling away at various connection points, creating a hazard. I have been quoted around $5-600 for the harness plus labor. I looked at a bunch of the connectors in the bay and I see what they are talking about. You can see small amounts of exposed copper at certain wire junctures. Is this some thing I can McGyver ( i.e. careful electrical taping of exposed areas myself) or is this critical that I have repaired?
2. Numerous minor oil leaks found. Front transmission seal leaks, lower section power steering gear leaks, both sides of differential output leak. Rear main hyropneumatic suspension valve wet. Quoted real high labor times, probably legit, to fix these various leaks. How critical are these?
3. Needs 4 rotors and brake pads ( 15% pad left).
Sorry for the long post. I would appreciate any feedback you folks may have, who have owned higher mileage ( mine at 121k) 300 series cars.
Thanks for the intellgent input.
Matt
Basically, all engine wiring harnesses on these 3.2 liter M104 engines are bad from 93-95. Here is a link with a great discussion on this issue:
http://www.mercedesshop.com/shopforu...iring+harness\
You really need to change this immediately. Common manifestations of a bad engine wiring harness are very numerous, but include and not limited to: various and random shorts in the electrical system; various, random, and meaningless engine fault codes; misfiring on any of the cylinders, an uneven idle, shorting out the ECU, computer, etc.
You really can't wait on this. Trust me. Letting this go can cause you thousands of dollars in damage. Your quote was right on. The wiring harness is $500 dollars and change, and the labor is 1-2 hours.
I have read many discussions between MB technicians on other websites, and basically two reasons for the bad wiring harness are noted:
1. MB tried out a new insulation to make the wires more recyclable or bio-degradable.
or
2. MB tried out a new insulation to make the wires resistant to rodents eating the wires.
In any event, it was a disaster and the insulation breaks down in the car. Many of these wiring harnesses were replaced by dealers under the original warranty or the Starmark warranty if the problem manifested.
As far as your other problems:
1. Various fluid leaks - I suppose these are just minor leaks, and can be tackled systematically one by one over time. Pick the worst one first, and then when you have the money, do the next one. Just check the fluid levels to make sure the fluid doesn't get too low. My buddy has a 95 E420, and just had his power steering pump rebuilt w/ new seals. The rebuild kit was $15.00. The labor was several hours. I'm very suprised your head gasket doesn't leak. The original gaskets leak oil at the right rear of the head. Replacement gaskets from the dealer seem to work without leaking.
2. Rotors and pads - MB rotors cannot be turned. The metal is very soft, and you will be replacing the rotors more often than other cars. Only use original MB or ATE rotors and original pads. Otherwise, your brakes will squeak badly. The rotors are available at the dealer for around $75.00 each, or you can buy them at mercedesshop.com for around $50 each. I would replace the front rotors and pads now, as they get the most wear. 15% pads left will probably last several months on the rear. Also replace the brake sensor when replacing pads. They're cheap. If you don't, your idiot light won't illuminate.
Don't let these repair / maintenance issues get you down. This car is 8 years old and probably has some mileage on it. Get the car up to speed, and it will give you many years of good service, and never show the wear that Japanese / American cars will.
People often say how expensive MB parts are, but in comparison, my Nissan Quest and Toyota Camry had higher parts cost on almost every similar repair I did. My dad's Buick also had higher parts cost for the rotors and EGR Valve than my MB.
Last, one other maintenance item to perform on these M104 engines is to have the hot inlet pipe to the intake manifold "reamed out" with a cable, like a speedometer cable and a drill motor. You may think I'm crazy, but this engine is notorious for engine fault codes indicating low egr flow. The average mechanic will send you on your way with a new egr valve, thinking that the egr was just closed shut. But the fault code will reappear. This hot inlet pipe gets clogged up with carbon from the egr vapors, restricting air flow. Many MB mechanics now include this on the 30,000 mile maintenance service. There is a great article on diagnosing engine fault codes at the mercedesshop.com website, I think under the DIY section, written by a master MB technician, 27 years, in Florida, that discusses this issue and how it was arrived at. The link to the article is here http://www.mercedesshop.com/diy_stevebfl_1.htm
Good luck, and let us know how you are doing as you tackle these problems.
Last edited by suginami; Mar 19, 2002 at 07:58 PM.
http://www.mercedesshop.com/shopforu...wiring+harness
Here's a link that talks about my problem with engine wiring harness:
http://www.mercedesshop.com/shopforu...wiring+harness
Here's another thread about the engine wiring harness. M.B.Doc, an MB technician, suggests 2-3 hours labor for the job:
http://www.mercedesshop.com/shopforu...wiring+harness
Another link, with picture that shows inspecting a wiring harness:
http://www.mercedesshop.com/shopforu...wiring+harness
And another:
http://www.mercedesshop.com/shopforu...wiring+harness
Last edited by suginami; Mar 19, 2002 at 08:10 PM.
I was quite suprised how rare W124 wagons are.
In 1994, total U.S. production numbers for the wagon were 2,513, and the original sticker price was $46,200. Wow.
Here is the link:
http://www.mbusa.com/brand/container...24568&menu=2_2
Suginami, thanks for the great info.
I feel better about things having read your replies. I got a little worried when I started looking at the list of issues and tallying up the $. However, long range I think you are right...get the car up to speed and then it shouldn't be too bad.
I appreciate the great info regarding the wiring harness. You have convinced me to have the work done asap on this one.
I will probably have all the brakes done at the same time, just because I am big on always having good brakes and tires ( safety). I try not to skimp on this kind of thing on any car.
I, too, found the sales numbers on the E320 Wagon for 1994 to be pretty interesting. Something like 2500 sold that year in the USA. Now that I think about it, I have not seen another one like mine in Kansas City ( silver-grey 2 tone with blue tex interior ).
Anyway, thanks a lot for the really informative response.
Matt
This tire is really the tire of choice.
I paid $137.00 each at the tire store near my house, but realized they are available at www.thetirerack.com right now for about $109.00 each. Cheap.
Last edited by suginami; Mar 20, 2002 at 12:07 PM.
I'm really frustrated. My car is currently getting its 120K Mile service and they want to charge another $650! to fix some sensor that monitors the "up shift O2 level(?). This is ridiculous!
Any ideas of what I can do, short of unplugging the light?
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