420SEL O2 Sensor Wire Location - PeachParts Mercedes-Benz Forum

wbain5280 · #1 10-06-2006, 12:37 PM

I've looked at the DIY article in the DIY section http://www.peachparts.com/Wikka/M103VacuumLeak but I cannot figure out where the wires are? Any help would be appreciated, pix, verbal etc.

wbain5280 · #2 10-06-2006, 01:12 PM

OK, I found it. The wires are behind the front foot panel on the lower left hand side. I checked the signal and it's a really low value or no value,so now I've got my local parts guy checking his older 3 wire O2 sensor supply.

wbain5280 · #3 10-11-2006, 12:24 AM

I bought a Denso generic three wire sensor on Tuesday and tried to get the old one out. It would not budge. I'm taking the car to the school on Friday and I'll have a go at it on the lift. My fave instructor says he'll have his class scope the old one for a signal. While I'm there, I'll replace the shifter bushings and do an underbody inspection. I know that the steering leaks but I don;t know where. In the mean time, I'll replace the injector seals and holders and the air bypass tubes. Maybe while I'm there, I can get an emissions check.

I've also got to get the underside cleaned, so I'm taking it to a spray wash place for a bath. The rear seal must be bad.

sixto · #4 10-11-2006, 01:47 AM

For some reason the power steering return lines have a much shorter life than the pressure line. There's a return line from the steering box to the cooling loop, and from the cooling loop to the reservoir. The fitting that screws to the reservoir can also leak.

Sixto
93 300SD

wbain5280 · #5 10-11-2006, 04:02 AM

Thanks, I'll definitly check that when the car is on the lift. When I was poking around looking for the O2 wires, I found a complete PS gear O-ring set under the front seat. I also have lots of low pressure PS hose that I can use to replace the existing hose. Maybe all I need to do is tighten the clamps.

wbain5280 · #6 10-12-2006, 12:12 AM

I took the car down to spray wash the underside. On the way, I witnessed a Ford Mustang GT crash into some fencing after going through a left hand turn too fast. Since I'm a good citizen, I stopped, as did someone else, to assist and call the Police. The guy was charged with reckless driving.

I got to the spray wash place and fed a huge number of quarters into the slot machine. I'm pretty sure I blasted most of greasy crud off the underside of the front chassis and engine. It should be much easier to work on the car on Friday at the car repair class. Shifter bushings, rear tires, change the engine oil (all 8 qts), and the list goes on.

I also cleaned some of the interior panels. They were filthy, it was really disgusting. How can someone let such a beautiful car get so dirty. I really need to replace all the seats as well.