:biggrin: No don't do that!!!! Rn through the fuel WIS items in the WIS Sticky first! I got some trouble shooting there ....

Incorrect fuel guage levels, etc.....

You were too quick .....  try now ! ... and I got 2 important ones I can't upload!  .... email me !   ... and ask the Admin to lift the upload LIMIT for me!

done! Doesn't show much except for the location .... Does say however that the SDS is needed when replacing it! Although this must not be needed (self reseting) according to others who have done CPS replacements

Here is a DIY to supplement the WIS I posted .... should only take you 5-10 min to replace

Crankshaft Position Sensor DIY

(CPS.JPG)

crankshaft position sensor - DIY.pdf (3KB - 8 downloads)

crankshaft position sensor - remove&install.pdf (254KB - 8 downloads)

CPS.JPG (52KB - 7 downloads)

cps - 01.pdf (33KB - 8 downloads)

Had a tech in Vancouver B.C explain how to test your CPS, if it starts to fail.

He said connect to an ohmeter, should read a steady 850-1200 ohms.

using an air heat gun, start warming the sensor (not hot,but warm as it's plastic), keeping a steady ohm reading, and it should not change much.

Mine started to go up fast to infinity, or just lose a reading. QWhen it cooled down, reading started.

Anyone have input for this test procedure? Also, he said if the CSP is suspect, watch the tach needle, as it should not jump when it is in the no start mode of the problem.

If the tach needle jumps, it is somthing else, not the CPS.

Again, anyone with knowledge about this test as well?

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In the 8 years I been at my tech's MB shop, I NEVER seen a bad CPS from the older MB, such as mine; 92 to 96 S or E class but he says that in the newer car 2001 and on, it gets replaced a lot.

It sort of boggles my mind, since it's just a magnet and coil of wire, so what can go bad?? Obviously, the heat must 'melt' the wire coating causing it to open.

Bottom line it must be poor quality control!

In the old manuals, the TEST for this part is JUST an ohmmeter calling for a 850 - 1200 ohms. No other test.

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The tech in Vancouver told me it should be around 1200 ohms. Another thing was to hold it steady and give it a slight tap , and see how far it jumps around before coming back, or if it just gives no reading at all. Mine was sensitive to tapping in certain areas of the sensor, closer to the magnetic end. One time, I had to touch the tip to a metal surface, kind of resetting it to get the ohm reading back

I tried testing the wrong new one sent to me, but because it was a diffferent #, it showed about 900 ohms. The correct new one I received today was around 1200 ohms, and as you mentioned, they increase with heat. The old one increased pretty fast around 1200 ohms,went up and up and then just crapped out until it cooled off a little, then read it again, crapped out as soon as the heat was put to it. The new one didn't increase dramatically when heated, just slowly went up. I never heated it much, but it seemed a bit more steady paced, when the old one just bounced right off the scale pretty fast. I am thinking maybe , especially on a warmer/hot day, the increase in temp around the sensor would cause the unit to fail faster, cut in and out more often, longer cool down time as compared to a colder, rainy day, when maybe it wouldn't even crap out at all? Just a thought, since we're dealing with a coil, or wire expanding with heat. I know on our snowmobiles, the CDI unit would do the same when failing, die when hot, reconnect inside and work again when cold, and eventually just die out completely. Tomorrow, I will take it on a drive, 120 km to another city, and back. I will post again what happens, if anything new, as it will be warm out again as well.

Failure to start:

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I got my car back yesterday, report from dealer indicates following:

Carried out test via diagnostic machine, no faults stored. Checked fuses and relays, Checked actual valves, cheked fuel pump activation, removed rear seats and checked connection at Fuel pump, Cheked fuel pump current consumption, cheked crank angle sensor signal. Checked continuity of wires to engine control unit, found connections for crank angle sensor loose on control unit causing engine to cut out. Removed most engine wiring harness and replaced wiring for crank sensor. Insulated wiring harness and refitted all parts, carried out extensive road test.

... and hope that you are not chasing a heap of things like the "fuel sender", "fuel pump" , etc.....   DId you add more fuel even though the guage was showing half full? ... If the "fuel sender" is broken , then it might show wrong levels in the guage? .....i.e you think it is half full , when indeed it is empty!

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Ahhh , then it really does sound like the CPS

... and no detailed removal/install pics & instructions noodles? ... shame on you man! 

 ... Sorry ... going to have to show you the "yellow" card for that one!