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ML320 - 2000
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Discussion Starter · #1 · (Edited)
I repaired my 2000 ML320 with 92k miles on it by replacing the CPS (Crankshaft Position Sensor) myself.

[photo of CPS]




The symptoms of the car were:
1. Occassionally, the engine would crank, but would not start. If I tried 3 or 4 times or came back 5 minutes later, it would finally start. Eventually, (over about 2 weeks time), the engine would crank but NEVER start. It didn't matter whether the engine was warm or cold.

2. One time the engine stalled while sitting at a traffic light idling. It took about 3 minutes before it would start again, and ran very rough for about 3 miles.

3. OBDII scan showed P0301, P0304 and P0300 (cylinder #1, #4 and random misfires respectively).


From reading the messages on this board, it seemed like the CPS was a candidate for replacement.

I 1st checked for good fuel pressure by simply loosening the fuel line in the engine compartment, WITH THE ENGINE OFF, just enough to feel fuel spurt out and tightened it up again. I did this about 2 minutes after I had turned the engine off. I had only run the engine for about 30 seconds (from a cold start) so that it wasn't hot but there was enough time to pressure the fuel line.

[photo of fuel line in engine compartment]




Replacing the CPs took about 1 hour:

Tools needed:
1. Torx E9 socket. Note though that no one sells an E9....therefore, a 1/4" 6-point socket with a 1/4" shaft fits perfectly. You must use a 1/4" shaft socket because a 3/8" shaft socket is too large to get into the small space available between the bolt and the body of the CPS.

2. 1/4" shaft to 3/8" shaft converter.

3. 10" extension bar. The 10" extension is the perfect length on the ML320 because it allows you to clear the engine block and valve cover (see photo below).

4. 3/8" socket wrench.

5. a 1/4" screwdrive type socket wrench is also helpful for putting the bolt back in during re-assembly.

[photo of tools used]




To replace, do the following:
1. remove the wire plug off the CPS. You can feel a little lever/latch on the plug, which when pushed, frees the connector.

2. Place the 1/4" 6-point socket, 1/4"-to-3/8" shaft converter, and 10" extension bar on the bolt head. Do this without the socket wrench attached for easier placement on the bolt because of the limited amount of room (see photo).

[photo of the 1/4" 6-point socket on the CPS bolt and the 10" extension bar extending beyond the engine block
.....view is looking toward the rear of the engine compartment on driver's side of the engine block
.....the valve cover and 3ea. spark plug coils are in the center fore-ground]




3. Then place the 3/8" socket wrench on the extension and remove the bolt.

4. You may have to use some muscle to get the CPS out of the bell housing, then clean the seating area so the new one will sit squarely when it is put in.

5. Place the new CPS in and position it properly.,

5. Use the 1/4" screwdriver socket and 1/4" six-point socket to start the bolt. Use the 10" extension and 3/8" socket to tighten it. DO NOT OVERTIGHTEN.

6. Place the CPS cable back on.

That's it, you're done.....mine fired right up and hasn't had a problem in over 2 weeks. It does seem that the engine was a little rough for the first 2 days or so, but seemed to smooth out nicely. Hopefully this was only the computer re-synchronizing to proper sensor readings from whatever it was receiving before.

Thanks to the forums in general for the info. that led me to this solution.

Here's a URL to another DIY explanation with a few good photos here.

-- rick s
[email protected]
 

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ML430 - sold
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929 Posts
Hi Richard,
Excellent write up - wish it was as easy for the V8's :-(
 

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2014 RX 350 F Sport, 2007 Scion tC, 2000 ML 430 Money Pit Finally Gone! Oh Happy Day!
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1,284 Posts
Good job....................................
 

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1922 Ford T no OBD, no ECU, no SCN
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37,842 Posts
What took an hour? Getting it via wheel well took less than that with good access on V8 engine.
 

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1999 ML320
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24,029 Posts
Great link for Crankshaft Position Sensor replacement on ML320
 

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ML320
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303 Posts
Tools needed:
1. Torx E9 socket. Note though that no one sells an E9....therefore, a 1/4" 6-point socket with a 1/4" shaft fits perfectly. You must use a 1/4" shaft socket because a 3/8" shaft socket is too large to get into the small space available between the bolt and the body of the CPS.
It's actually an E8 Torx Socket. I got mine from NAPA Auto Parts for about $3 each.
 

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'16 GLE350, '14 E350 Sports, '14 GLK350, '02 ML500, '01 ML320 & '96 C280
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123 Posts
Anyone has the pictures ?
I am trying to do this.. but can seem to load the pictures.
 

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2000 ml430, 99 infiniti i30 limited edition
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980 Posts
Anyone has the pictures ?
I am trying to do this.. but can seem to load the pictures.
1. Loosen driver side front wheel lugs
2. Jack up the vehicle ( driver side )
3. Remove driver side front wheel
4. remove wheel well lining with size 10 socket
5. remove heat shield
6. look for the cps, disconnect cable
7. loosen bolt with t8 socket
8. pull out bad cps
9. install new cps
10. reinstall bolt (pain in the butt)
11. reinstall cable
12. the end
 

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'16 GLE350, '14 E350 Sports, '14 GLK350, '02 ML500, '01 ML320 & '96 C280
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123 Posts
thank you for the reply.
as I am a beginner, I still have no idea where it is locate at ?
is there any picture shows the specific location ?
 

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Outstanding Contributor
2006 ML500 2002 ML320
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17,655 Posts
thank you for the reply.
as I am a beginner, I still have no idea where it is locate at ?
is there any picture shows the specific location ?
What kind of vehicle are we working with? Is it a 96 C280 or an ML. Whatever it is please update your profile on the left to include the year and model of your vehicle, and also let us know where you are from.
 

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'16 GLE350, '14 E350 Sports, '14 GLK350, '02 ML500, '01 ML320 & '96 C280
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123 Posts
many thinks to rimasl2 - Richard,

He stopped by and show me where it is located, saved me at least an hour of time.

However, I later found out the 8mm socket is too big. and 6mm is too small. I did not want to go out to get a 7mm. so I tried the 1/4 in socket. It fits fine, I was lucky that I did not strip the screw.

After I got the screw out, its a torx.

please see attached screw.



After the replacement, I erased the code P0335. and the car drive so smooth and feel like more torque.

Again, thanks you Richard
 

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2003 S55K, 2002 W220 S430 (RIP), 1999 W163 ML430, 2004 W230 SL500 Sport
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49 Posts
Thanks for the info. I ended up ordering a "Camshaft position Sensor" which goes in the front. I guess it is the "Crankshaft position sensor". Could not find it so I will use the wheel well method since I have the V-8..
This time I will get the part from the dealer. The none Bosch Camshaft PS did not work...
 

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1998 Ml 320E
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11 Posts
Any tips on how to remove a CPS that seems stuck in there...........can't even seem to pry it with a screwdriver.
 

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Dallas, Texas
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10,094 Posts
Any tips on how to remove a CPS that seems stuck in there...........can't even seem to pry it with a screwdriver.
Douse area with rust penetrant, let it sit then try turning it. Sensor has ferrous core. If corrosion got inside it has swollen.
 

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2005 E320 CDI, 2016 E250
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3,199 Posts
Lisle Socket Set for External Torx - 26750 at Sears.com

This is the set I bought for removing seats and various other portions of the truck...for $20 it has come in QUITE handy. Also I found this set is a part of the 48 Peice Craftsman set I have.

As for getting out the CPS when stuck...as Witek said - I would use PB Blaster...works great.
 

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1998 ML320
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155 Posts
I'm having trouble finding my CPS and determining which one I should order. Does anyone have some good pictures of the location? The original pictures in this thread aren't showing up anymore.
 

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'16 GLE350, '14 E350 Sports, '14 GLK350, '02 ML500, '01 ML320 & '96 C280
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123 Posts
you dont have to take out the tires & fender cover. since you have the part on hand you know how it is pluged in, just get a mirror and you should be able to feel around and find it.
 
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