I'm helping a friend clear a check engine light code for the camshaft position sensor in a 1997 E320. I need to check the sensor and wiring and reset the CEL.

Can somebody please post a wiring diagram to tell me where the wire going to the camshaft position sensor ends up. I'd like to check continuity to be sure the wire is well insulated and not broken in the harness.

Also, is there a way to check the functioning of the position sensor without having an oscilloscope. I assume it works by sensing a magnet on the camshaft gear passing by. Not sure how to easily measure that event.

I'll also check that it has the 0.4 - 0.6 mm gap between the end and the camshaft (gear?).

Thanks,

Paul

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1983 500 SL (Gone )
1972 350 SL 4.5

that there is a need to verify this clearance?

CPS signal is .8-1.5 a/c V. at crank/idle rpm.

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A Dalton

looks like you might be out there this evening. Saw something in another of your posts about verifying the gap on a CPS. Is it an issue with this model of car (1997 E329)? If so, do shims come with replacement unit and how is it done as sensor looks like something that inserts into the cam gear cover. Thanks.

If the sensor signal meets Voltage specs, then the spacing is OK.
If you change the sensor, then you want to check the spacing for clearence [.5mm/ .020"]. There are spacer/shim washers that go between the sensor and the mounting hole to make that adjustment.

Don't confuse the cam sesnor and the cam advance magnet...they are completely different, and often confused. The advance is on te front and the cam sesnor is on the side.....

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A Dalton

my car is throwing code P0341. Went to run some arrands this PM and on the way out it missed badly which has never happened. On the way back, it stumbled at startup and when i got it out on the road, I accelerated briskly to see what would happen. Car ran very roughly and turned on CEL. I pulled codes when I got home (Car ran roughly all the way but it was a short distance). There was also a Cylinder 2 Misfire code in the memory. Think I should try a new camshaft position sensor it connections are clean and tight?

I would change the 3 plug connectors a under the coils..common , maint. item and the most common cause of mis-fire on 104 DIS ignitioned engines

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A Dalton

my under-the-coil connectors are only about 20,000 miles old but I will replace them.

Thanks Arthur,

I'll check the AC volts for sensor function.

Any help on checking wiring? I'd like to verify continuity. Where do they lead, what pins on computer??

ALso, clearing the code using a OBDII meter rest the CEL but left the code in the computer. The CEL returned, and I'm not sure if this means there is a problem with the camshaft position sensor or circuit, or if I need to clear the computer entirely. This time I'm going to use the battery method, to verify I can get the code to disappear. Then if it comes back I will know it isn't a one-time fluke!

thoughts?

Paul

__________________
1983 500 SL (Gone )
1972 350 SL 4.5

If they are that new , I would hold up on changing them.
Does the car have Plats??????


For original poster:

The sensor should ohm out at 900-1600 ohms. I don't have the pin #s for that chassis.

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A Dalton

no my car has OEM plugs, Bosch F8DC4. After pulling the first set of codes, I cleared them and as I was putting car in the garage, CEL light came on again.
Just pulled that code this morning and again see CYLINDER 2 MISFIRE. Car started fine and ran smoothly but goes to rough idle about 15 seconds after startup. Is cylinder 2 one of the ones which uses the short connected under the coil? Thanks.

Swap that coil with one of the others and see if the code follows the coil.

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A Dalton

after looking at my records, I discovered that the plugs and coil-to-plug connectors had about 40k miles on them. So I got three new connectors from dealer and replaced them and all plugs today. Car seemed to run very smoothly upon startup so I went for a drive. After a couple of miles and while accelerating up a grade, CEL came on and car went to rough idle at the next stop. Drove home and again read out code P0302 (CYLINDER 2 MISFIRE). This was third time it has come up after clearing it the previous two times. The code concerning the camshaft position sensor has not returned after the initial appearance. Is it possible that the coil serving Cylinders 1 &2 is defective? Can anybody explain how one coil is made to serve two cylinders?

Like I told you on the last post...swap the coil with one of the others and see if the code follows the coil swap....... Simple.

You have a Waste Spark Ignition using one coil to fire two plugs that are wired in Series..... a Series Circuit.

Use the Archieves ,,,there are pages upon pages on this .

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A Dalton

Back to the 1997 E320 camshaft position sensor issue!

I went to check for the 1 kilo-Ohm impedance, and 1 V AC in idle of the camshaft position sensor. I found that the sensor had three terminals, not two as I expected
The resistance was very high across each terminal pair - like 100 KOhm or more (open circuit)

and when the car was started, I could detect no AC voltage at all between any pair of terminals.

Arthur?? I don't understand how the sensor works, and I'd like to see if it functions.

I tested the CamPS on our family car (2 terminal) and it measured 2 kOhm just like Arthur said.

Is anybody familiar with tests for the three terminal sensors - or does this one sound like it's dead?

Also, could the magnet have come off the camshaft gear sprocket?

TIA,

Paul

__________________
1983 500 SL (Gone )
1972 350 SL 4.5