sl3204me

I have a 1995 SL320 with 92,000 miles and while jiggling the wire gently leading into the MAF meter,the wiring started melting and smoking in my hand.
I turned the ignition off and thoroughly inspected the wiring.All of the insulation covering the wires inside the wiring jacket was totally disintegrated.
One big short circuit.My question is this.Is the wiring going from the air flow meter back into the main engine computer area a sinle replaceable harness or is this a part of the entire main engine wiring harness.MB says it can't be replaced by itself,but only as an entire engine harness replacement costing $850.Does any MB wiring expert out there know for sure?

saturnstyl

You had better check the rest of the wiring. There is an extremely high liklihood the rest of the wiring is failing also. An entire engine harness is usually the best repair.

BenzVince

Yikes, why is a wire harness is melting, that's odd. Now if you were touching the MAF with your bare hand yes it's gonna mess up since it's sensitive if you have touched it cuz your hand has oil gland, and if it' touches it's gonna mess up and throw an engine check light. Sorry to hear that. MAF are not cheap. I know about them since i read a lot on the Maxima.org forum and I have a Maxima as well and never happened to me but a lot of org member had a rash of problem. The cost was unimaginable to replace.

sl3204me

I have decided to go ahead and replace the entire engine harness myself with my able brother's assistance.(Electrical engineer).I took off the MAF meter itself and cleaned the entire interior carefully and the wire inside the meter seemed to be intact and not broken or worn.It appears that the short was between the wires inside of the wiring harness itself.I talked with the service Advisor at Mercedes and got him to admit that the 94-97 SL models did have a problem with the wiring underneath the hood.It appears that MB had outsourced the manufacturing of these harnesses to a company who was following environmentally sensitive biodegradable regulations at the time.In other words,the harnesses were made to disintegrate in case they made it to the local landfill so as not to adversely affect the environment.Unfortunately their calculations were done on a 10 year timeframe,not a 30 year timeframe.The harness was eventually upgraded somewhat ,but MB does not want to help out those of us who got stuck with the old harnesses in replacing them.After much discussion with MB I did get them to reduce their price for labor,but I have decided to just do it myself.If you do need a new MAF meter you can get one for about $280 now on the Internet brand new.

saturnstyl

It wasn't just the SL. Virtually all the models for several years had engine harnesses that would crack and fall apart. For a while benz was replacing them... then I guess they just decided they were old enough to not have to support anymore. Replacing the harness really isn't that hard, just try not to cut anything out, take your time and route it properly.