triggerman

Guys

Fri night I noticed that upon decelaration there was a new slight vibration. Well it has gotten progressivly worse and is now accompanied by harsh idle and no acceleration power and a slight rubber burning smell comming from engine compartment. I dont think its the trans as it will run rough a vibrate when stoped and in park. Has NO power under acceleration and will hardly get out of its own way. The only thing I have done is remove the wrong application Autolite spark plugs the PO installed and put in the correct Bosch Supers F8DC4. This problem began Fri night and I installed the plugs Sat morn. so I dont know if that has anything to do with it or not. I anyone has had Any similar problems, Please help as we depend on this car to get to work.

Thanks
Adam

neanderthal

go over the work that you did and make sure you got the plugs in correctly
and that the spark plug boots are firmly affixed tot he spark plugs
and that the wires arent being burnt by the exhaust manifold.

check for blockages in the intake tract
run some fuel injector cleaner
take of the distributor cover and see what condition the rotor is in. also check the contacts.


any number of things can cause a car to start to run badly. the first thing you always do is cover the basic maintenance (oil change and tune-up) parts; oils, plugs, wires, filters, rotor(s), cap. this will normally sort out whatever your problem is.

from there it gets expensive.

triggerman

Thanks for the suggestions. My 124 has the M104.992 motor which has coil packs and no dist, cap, or rotor. Thats what makes it so weird; after my initial post I went out and took off the engine cover and made sure all the wires were plugged up, even took some off and put them back on. buttoned everything back up and the car runs 95% better! Have NO Idea what I may have done to improve anything? The only issues I have now is a slight vibration while accelerating beginning around 2200 RPM that goes away quickly above that, and a clicking sound, comming from under the gear shifter/ashtray area, when I let of the gas from full speed. This sound instantly goea away the second I repress the accelerator and returns the second I let off again. Got me stumped .

Thanks
Triggerman

ebennz

how many miles on purchase?

miles now?

how long have you owned it?

have you ever changed ALL of your fuses?

it's VERY CHEAP insurance.

exactly what maintenance stuff have you had done and by whom-indy or mb tech?

does car still have original main engine wiring harness?

crr1612

what does changing all the fuses do?

triggerman

The car has 176,000. miles and I have owned it for 1 month. I really do not know if the fuses or wiring harness have been changed or not. The only thing that I personaly have done is an oil change and sparkplug replacement. At this point MOST of the time the car is running great, the only new thing that is hanging around semi-permantely is the ticking sound comming from under the gearshifter/ashtray area. I'm going to have it checked out tomorrow by an indi mech that actually specializes in MBs and other Germans, so well see. And yes BTW, what exactly does changing all the fuses accomplish?

Thanks
Triggerman

Brian McL

...pretty good chance it is the wiring harness. It tends to rear it's ugly head just after changing the plugs. As you lift the plug connects/coils out and lay them up and out of the way the brittle inside wire coatings start to let go...shorts result and performance is bad....or any number or other weird manifestations present themselves. If you can, find an exposed wire (like at the temp sensor on the thermostat housing) unwrap the outer tape and check the insulation on the inside wires. If they are brittle and fall apart in your hand then the harness is shot. To confirm...unwrap the harness at one of the leads to a plug wire...it will most likely be the same. Don't waste your money getting opinions...get a new harness and put it in yourself...it really is very easy. Check out this link: http://www.mercedesshop.com/Wikka/M104WireHarness
With your mileage you probably still have the original harness....and it probably is garbage.

Brian McL

...oh...and once you get that engine wiring harness fixed...the next "surprise" you can look forward to is the throttle body wiring harness. It too suffers from premature deterioration. There is a lot of information on the forums about the wiring harness issues associated with the W124's with the M104 and the M119 engine. Small price to pay for an otherwise great car.

triggerman

Well I was afraid this day would come, just hoped it would be further down the road. So is the stealership the ONLY place to purchase said harness, or do some of the online parts places have it?

Mine is acting exactly like has been described. Only acts up sometimes and sometimes it feels like a new E55 (well, thats pushing it!). I think I will not get an appointment at the shop tomorrow.

Thanks very much
Triggerman

Brian McL

....yup...the only place to get the harness is the dealer. Shop around...call a few or even MB USA...don't tell them you just bought the car though. Work the sympathy angle and maybe you can get a discount. You should be able to get one for $600. Anyway, get it and install it yourself. Get it over with.

ebennz

seek fellows, you will find...

the first fuse to go will be the one that controls tach, temp and fuel gauges.

they corrode and deteriorate. they only cost about .18 cents each.

change them all

http://www.mercedesshop.com/shopforu...earchid=647183

triggerman

Decided to go ahead and take the wagon to the shop and have it checked out by the Benz mech. As soon as it went up on the lift he said "Oh man look at this!" The dampener between the driveshaft and trans (MBs version of a U-joint) was no longer there! you could grab the driveshaft and spin it a quarter turn in relation to the trans. Also rear trans mount is crumbling. He said I was lucky the driveshaft didnt come through the floor, or worse crack the trans housing. Should be fixed tomorrow.

This should be about 90% of my recent problems, but they said yes I do need a harness. I have called 6 different MB dealers in my region and recieved the exact same price from all of them, $1010. If anyone knows of a dealership that will work with you on price, or an aftermarket harness that exists, Please Please let me know, M104.092 engine (not to proud to beg).

Yawl go out and check your dampener if you havent!

Thanks for all the help on this guys
Triggerman

neanderthal

i think youre talking about what mercedes calls a hardy washer, bmw calls a guibo. its a rubber drivetrain "shock abosorber." pretty easy fix. get both done while youre there.

as for the harness, check with some of the parts vendors on various mercedes forums

triggerman

Yea thats right, also called a "flex disc" by the parts guy.

Triggerman

triggerman

Well got my car back today and let me tell you, that flex disc was'nt 90% of my problem, at this point it was 100%!! This thing thinks its an AMG again! No hesitation, vibraion, or anything for now. I know I still need the harness, and I'm going to do it, but at least its not as urgent as it seemed a few days ago. Dropped over $500. is nothing but maintance issues, serp. belt, flushing of break system, rear trans mount, flex disk, labor, and a charge to take me home 20 miles yesterday when the car could not be driven. All is well for now.

Thanks for the help guys.
Triggerman

Boatdiver

Thought this'd help. I got mine in just a couple of days, great service, no tax and free shipping. When I told my dealer the "fullday job" took me 1/2 hr. they basically thought I was full of it.
http://www.autopartsworld.com/new/pr...-420&x=92&y=12

triggerman

Thanks for the help, but that link is for a 420 V8, I have the 320 I6. Cant imagine why this little 6 harness is so much more expensive and ONLY available from the dealer, as compared to the V8 versions.

OH well
Triggerman