How to replace a Crankshaft Positiong Sensor
Thread Starter
MBWorld Fanatic!
Joined: Feb 2010
Posts: 1,506
Likes: 130
From: Bolingbrook Illinois
1999 C43 Amg
How to replace a Crankshaft Positiong Sensor
I've read and watched YouTube on how to do this and found that everyone takes a long time to replace this. So I wanted to share a very simple way of doing this.
It's a lot of reading but only because I want to give every detail possible. If I was showing you face to face I could explain it in no time..
You will need an E8(I believe) I used a regular 1/4 size Socket (TALL ONE,very important) and a 1/4 ratchet.
-Must have engine COLD.
-Remove air box
- Disconnect the wire Clip that goes to the sensor.
Press the right "tab" with index finger while moving the connector side to side and pulling up. This will loosen the OTHER tab on the other side of the connector which is hard to press.
- Put a flash light to see the sensor and run your hand down there and feel the screw. This will give you and idea where it is and makes it easier to put the socket on the small bolt.
- Now put your socket to the wrench and slide it down and line up the socket to the bolt. Remember that the bolt is a little slanted so slant the wrench toward you a bit as you try lining it up.
NOTE: the wrench handle has to be facing the firewall as you slide it down. This will give you room to turn and loosen the bolt. Any other way and you won't have room to turn.
- Once you loosen the bolt remove the socket from the wrench.
- Finish turning the bolt with just the socket.
- After like 2-3 turns lift the sensor till it stops. Now loosen another 2-3 turns and lift the sensor again. Continue till sensor comes out along with the bolt and socket. Take your time so you don't drop the bolt.
- To install the new one, visually look where the whole is where the new sensor will be sliding into. With the right hand bring down the sensor with the bolt on it.
- With your index finger as you go down find the hole and guide the sensor in all the way down gently. NOTE: Make sure the sensor bolt will end up facing straight at you. This lines up the bolt to the hole. Now use your tall socket and start turning the bolt all the way till its tight.
- Bring up the socket and attach it to the wrench. Make sure the wrench handle is facing the firewall as you go down. Now just tighten the bolt.
- Connect the wire to the sensor and your done.
It literally takes me less than five minutes to change one of these.
No need to remove air mass sensor or special tools, etc...
Hope this helps someone.
It's a lot of reading but only because I want to give every detail possible. If I was showing you face to face I could explain it in no time..
You will need an E8(I believe) I used a regular 1/4 size Socket (TALL ONE,very important) and a 1/4 ratchet.
-Must have engine COLD.
-Remove air box
- Disconnect the wire Clip that goes to the sensor.
Press the right "tab" with index finger while moving the connector side to side and pulling up. This will loosen the OTHER tab on the other side of the connector which is hard to press.
- Put a flash light to see the sensor and run your hand down there and feel the screw. This will give you and idea where it is and makes it easier to put the socket on the small bolt.
- Now put your socket to the wrench and slide it down and line up the socket to the bolt. Remember that the bolt is a little slanted so slant the wrench toward you a bit as you try lining it up.
NOTE: the wrench handle has to be facing the firewall as you slide it down. This will give you room to turn and loosen the bolt. Any other way and you won't have room to turn.
- Once you loosen the bolt remove the socket from the wrench.
- Finish turning the bolt with just the socket.
- After like 2-3 turns lift the sensor till it stops. Now loosen another 2-3 turns and lift the sensor again. Continue till sensor comes out along with the bolt and socket. Take your time so you don't drop the bolt.
- To install the new one, visually look where the whole is where the new sensor will be sliding into. With the right hand bring down the sensor with the bolt on it.
- With your index finger as you go down find the hole and guide the sensor in all the way down gently. NOTE: Make sure the sensor bolt will end up facing straight at you. This lines up the bolt to the hole. Now use your tall socket and start turning the bolt all the way till its tight.
- Bring up the socket and attach it to the wrench. Make sure the wrench handle is facing the firewall as you go down. Now just tighten the bolt.
- Connect the wire to the sensor and your done.
It literally takes me less than five minutes to change one of these.
No need to remove air mass sensor or special tools, etc...
Hope this helps someone.
Junior Member
Joined: Dec 2013
Posts: 42
Likes: 2
C43 ///AMG
I've read and watched YouTube on how to do this and found that everyone takes a long time to replace this. So I wanted to share a very simple way of doing this.
It's a lot of reading but only because I want to give every detail possible. If I was showing you face to face I could explain it in no time..
You will need an E8(I believe) I used a regular 1/4 size Socket (TALL ONE,very important) and a 1/4 ratchet.
-Must have engine COLD.
-Remove air box
- Disconnect the wire Clip that goes to the sensor.
Press the right "tab" with index finger while moving the connector side to side and pulling up. This will loosen the OTHER tab on the other side of the connector which is hard to press.
- Put a flash light to see the sensor and run your hand down there and feel the screw. This will give you and idea where it is and makes it easier to put the socket on the small bolt.
- Now put your socket to the wrench and slide it down and line up the socket to the bolt. Remember that the bolt is a little slanted so slant the wrench toward you a bit as you try lining it up.
NOTE: the wrench handle has to be facing the firewall as you slide it down. This will give you room to turn and loosen the bolt. Any other way and you won't have room to turn.
- Once you loosen the bolt remove the socket from the wrench.
- Finish turning the bolt with just the socket.
- After like 2-3 turns lift the sensor till it stops. Now loosen another 2-3 turns and lift the sensor again. Continue till sensor comes out along with the bolt and socket. Take your time so you don't drop the bolt.
- To install the new one, visually look where the whole is where the new sensor will be sliding into. With the right hand bring down the sensor with the bolt on it.
- With your index finger as you go down find the hole and guide the sensor in all the way down gently. NOTE: Make sure the sensor bolt will end up facing straight at you. This lines up the bolt to the hole. Now use your tall socket and start turning the bolt all the way till its tight.
- Bring up the socket and attach it to the wrench. Make sure the wrench handle is facing the firewall as you go down. Now just tighten the bolt.
- Connect the wire to the sensor and your done.
It literally takes me less than five minutes to change one of these.
No need to remove air mass sensor or special tools, etc...
Hope this helps someone.
It's a lot of reading but only because I want to give every detail possible. If I was showing you face to face I could explain it in no time..
You will need an E8(I believe) I used a regular 1/4 size Socket (TALL ONE,very important) and a 1/4 ratchet.
-Must have engine COLD.
-Remove air box
- Disconnect the wire Clip that goes to the sensor.
Press the right "tab" with index finger while moving the connector side to side and pulling up. This will loosen the OTHER tab on the other side of the connector which is hard to press.
- Put a flash light to see the sensor and run your hand down there and feel the screw. This will give you and idea where it is and makes it easier to put the socket on the small bolt.
- Now put your socket to the wrench and slide it down and line up the socket to the bolt. Remember that the bolt is a little slanted so slant the wrench toward you a bit as you try lining it up.
NOTE: the wrench handle has to be facing the firewall as you slide it down. This will give you room to turn and loosen the bolt. Any other way and you won't have room to turn.
- Once you loosen the bolt remove the socket from the wrench.
- Finish turning the bolt with just the socket.
- After like 2-3 turns lift the sensor till it stops. Now loosen another 2-3 turns and lift the sensor again. Continue till sensor comes out along with the bolt and socket. Take your time so you don't drop the bolt.
- To install the new one, visually look where the whole is where the new sensor will be sliding into. With the right hand bring down the sensor with the bolt on it.
- With your index finger as you go down find the hole and guide the sensor in all the way down gently. NOTE: Make sure the sensor bolt will end up facing straight at you. This lines up the bolt to the hole. Now use your tall socket and start turning the bolt all the way till its tight.
- Bring up the socket and attach it to the wrench. Make sure the wrench handle is facing the firewall as you go down. Now just tighten the bolt.
- Connect the wire to the sensor and your done.
It literally takes me less than five minutes to change one of these.
No need to remove air mass sensor or special tools, etc...
Hope this helps someone.
Useful information. What issues you faced which forced you to change the CPS?
MBWorld Fanatic!
Joined: Mar 2010
Posts: 5,889
Likes: 323
From: Land of mountains, cheese, chocolate and watches
12' W204 C63 AMG coupe "T-Rex", 12' W451 Smart Fortwo Pulse (99' W202 C43 AMG + Ultima Can-Am sold)
Usual sign that the CPS is on the way out is difficulty/impossibility of starting the engine when hot. When cold it starts normally. Could be other signs for a faulty CPS but I don't know them.
Thread Starter
MBWorld Fanatic!
Joined: Feb 2010
Posts: 1,506
Likes: 130
From: Bolingbrook Illinois
1999 C43 Amg
It was not but the car did start better and ran/runs better with the new one.
3 days ago I heard the air pump kick in for a split second than it turned off.
So I found out that the relay to the air pump goes bad.... So I changed it and so far the car no longer drops the idle.
Thread Starter
MBWorld Fanatic!
Joined: Feb 2010
Posts: 1,506
Likes: 130
From: Bolingbrook Illinois
1999 C43 Amg
Look at the link below and go down to post #8.
http://www.mbclub.co.uk/forums/elect...per-relay.html
http://www.mbclub.co.uk/forums/elect...per-relay.html
Last edited by speed43; Oct 15, 2015 at 07:11 PM.
