I am new to using a multimeter. Where would I check on the four pin?

Don't bother. You need to test the fat 4-pin sensor - diagonally.

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A.S.E Tech A1,A6,A7,A8 & MVAC 609 + EPA 608

Unless stated otherwise, any question I ask is about my greymarket 1985 380SEL.

Set it to ohms, less than 20,000, and touch the probe tips to the sensor contacts diagonally from each other. You should get roughly the same reading.

You're testing the sensor itself, not the connector.

__________________
A.S.E Tech A1,A6,A7,A8 & MVAC 609 + EPA 608

Unless stated otherwise, any question I ask is about my greymarket 1985 380SEL.

2.77 and 2.88

I guess we can check another thing off the list. Irritating, but at least you are saving me money.

Thanks

So I mentioned the Crank Position Sensor earlier. I tested inside the plug, and it was right, but I didn't test to ground. How would I do that and what should the numbers be?

Sounds like you tested the wrong component. The blue base, 2-pin sensor you tested is the CTS for high aux fan operation. You want the big 4-pin CTS with a fat black connector, located on the driver side back at cyl 6. Pull off the black connector, and test ohms on diagonal pins at various engine temps. Compare results against the table shown in the FSM. That CTS is actually 2 identical thermistors contained in a single assembly. Pins 3 and 4 are ground, 1 and 2 are signals. One signal goes to KE controller, the other to the EZL controller. The values you get from testing diagonally should be virtually identical to one another at each temp point, indicating that both the fuel and ignition management computers are getting the same readings at the same temps, but from different resistors.

Edit: Sorry, I just noticed that you already figured this out. But you really need to do the test at various temp points to know that the resistors give good readings throughout the entire operating temp range of the engine.

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1988 California version 260E (W124)
Anthracite Grey/Palomino
Owned since new and still going strong and smooth
MBCA member

Past Mercedes-Benz:
1986 190E Baby Benz
1967 230 Inherited from mom when she downsized
1959 220S Introduced me to the joys of keepin' 'em goin'

There are only 10 kinds of people in the world--those who understand binary and those who don't

Ok I finally put the fuel filter in.

I was going over the engine again and I found a wire that was broken. One side goes down into the battery area and I couldn't see where it went. The other side is plugged in to the side of the transmission. It is just plugged in. I tested with a multimeter to make sure I was looking at the right wire. I patched it back together. I did a 10 min test drive with the car and no problems. Anyone have an idea what it is I fixed? I have attached a picture of the wire and where I found it along the firewall.

Attached Thumbnails

 

Oh another thing. The wire was white and red. In case that helps.

I have attached a picture or where the wire plugs into the transmission. It looks to have two steel lines coming into the little block on the side of the transmission. This is from the drivers side of the car.

Attached Thumbnails

 

I think I didn't fix the problem.

I have a leak coming from my transmission that only leaks, but quite heavy, when my car gets over 40mphs. Not really sure what is going on. But I cleaned up the transmission and went out for a test drive to get it to leak so I could see where it was coming from. I had to get up to that speed pretty quickly in the area I had to do it, so I might have pushed the car a little too hard for about 30 seconds or so. I then came to a stop sign. After stopping I then made a right turn and tried to speed up. I was pushing on the gas but the car was just creeping along until I could pull into a parking lot. I waited there for a minute. The car never died which made me think it was not the same problem. I then drove off and it was fine. If you know anyone that wants a nice 91 300te 4matic let me know. Also anyone that might have an idea on, my transmission, what that wire is, and this other issue I would love to know.

Only white wire with a red stripe I could find goes to the intake air temp sensor...

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A.S.E Tech A1,A6,A7,A8 & MVAC 609 + EPA 608

Unless stated otherwise, any question I ask is about my greymarket 1985 380SEL.

Did this ever get resolved?

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1989 300E 144K

No I didn't. I have a friend who is a mechanic and he is looking at it when he has time. I am not sure which you are asking about. I never got a clear answer on what that wire is. I am still not sure where the leak is coming from, and I also still have the no start issue intermittently.

Asking $2000 for the car if anyone is interested.
That is with new plugs and rotor. New OVP. New O2 Sensor. New Water Pump. Rear wheel bearings are both new. Some new brake parts. Engine and transmission really run well, when it is running.

The weird thing is since I put the new OVP in the no start issue is a lot less frequent.

Oh and a new Fuel Filter as well.

You could always trace your wiring... May have a rub in the harness, bad solder joint at the socket or some other reason for intermittant contact.

Does it ever die or does it just not start?

__________________
A.S.E Tech A1,A6,A7,A8 & MVAC 609 + EPA 608

Unless stated otherwise, any question I ask is about my greymarket 1985 380SEL.