73 280SEL 4.5 Injection Wiring Harness

[alabbasi]

Does anyone know where I can get one of those for my car. My Mechanic has informed me that this part is shot to pieces and as a result the FI/Ignition is displaying some very irratic behaviour.

[wbain5280]

Why not rewire it yourself? Get some heat shrinkable tubing, engine wire of various colors (high temp insulation), soldering iron, solder and wire cutters. You will also need some loom covers. Lay the harness out, replace each wire piece by piece keeping the harness in proper orientation.

[alabbasi]

If it is that simple, I may try it.. I have a friend who is a Physics professor, I am sure he can supervise me.

[ADow]

Al
How did you go with this project? Did you end up DIY or did you find some other solution?
Alastair

[cth350]

that's the harness I sent you. Or is it a combination of that one and the original.

If you can read a schematic and handle an iron without burning your fingers, it's time consuming, but straight forward to fix.

-CTH

[alabbasi]

Charles

My Mechanic Chris used a compination of your harness and my old one to make a good one. I also have another spare harness that I pulled of 280SEL with a computer , fuel rail and injectors. Once we put the computer and the harness on, the car ran like a train. I think in the end, although the harness was cracking, it was not the issue causing the bad running, that was probably the computer. This car now runs like a train (and looks pretty sweet too with its new paint job).

Thanks for getting that to me.

[Tomguy]

If my 4.5 weren't so badly rusted, I'd have made a new one for myself by now. This site I ordered sleeving from for my PC is pretty cheap. I could make a new one in probably 4 hours for under $30.

[alabbasi]

[cth350]

Tom, cool site for cale wrapping. Keeping wires cool and safe from solvents is important under the hood. Though the high end shrink wrape is an astounding 800$/spool, there is plenty of affordable stuff there. I've seen way to many cooked wire harnesses carring unswitched power between the stater, alternator and the ignition.

-cth

[Tomguy]

Yeah, prices on stuff range from highly affordable to absurdley expensive. Although I'd imagine that fiberglass stuff would last forever! If I got a rust-free chassis to put my drivetrain into, I'd surely make a new wiring harness when I made the injection system a Megasquirt... with the ability to quickly change it back to stock by switching a few plugs if anything ever happened to the MS while driving!

[Bigmack]

Originally Posted by alabbasi

Does anyone know where I can get one of those for my car. My Mechanic has informed me that this part is shot to pieces and as a result the FI/Ignition is displaying some very irratic behaviour.

Did you have any luck finding this or somewhere to get one made?

[alabbasi]

A fellow forum member hooked me up with a wiring harness. I do believe that the classic center does still sell these items.

[Rauchen]

Originally Posted by alabbasi

Charles

My Mechanic Chris used a compination of your harness and my old one to make a good one. I also have another spare harness that I pulled of 280SEL with a computer , fuel rail and injectors. Once we put the computer and the harness on, the car ran like a train. I think in the end, although the harness was cracking, it was not the issue causing the bad running, that was probably the computer. This car now runs like a train (and looks pretty sweet too with its new paint job).

Thanks for getting that to me.

What do ya mean a computer on a 72 280 se. do you have aftermarket EFI?

[alabbasi]

Originally Posted by Rauchen

What do ya mean a computer on a 72 280 se. do you have aftermarket EFI?

These cars have an ECU located by the right headlight. The ECU was bad, I replaced it with another ECU from another 280SEL.

[RC4U12]

if you dont mind it not being original..Its easy to rewire..Theres not that many wires and just nees the connectors for the injectors and sensors..I did mine in about 5 hrs with soldering..I did use a new self built computer{mega-squirt} but the concept is exactly the same.. http://www.benzworld.org/forums/attachments/r-c107-sl-slc-class/227280d1236954531-rewired-engine-bay-engine-wire-start.jpg .. http://www.benzworld.org/forums/attachments/r-c107-sl-slc-class/227281d1236954531-rewired-engine-bay-engine-wire-done.jpg