2000 E320 P0115 Code
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Joined: Dec 2002
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From: LA
W210 E320
2000 E320 P0115 Code
Coolant Temperature Sensor DIY
Removed D ring (without removing thermostat) and took out the old CTS. Quick spurt of coolant jumped out at me, nothing too bad.
Had a lot of trouble installing D ring back on with the new CTS - no clearance to put it back in.
Slightly loosened the thermostat so that I can have clearance to put the D ring back in. When I started tightening everything back up I started noticing that coolant was leaking at the bottom of the car. At this point i realized there was a lot of pressure somewhere so I unscrewed the coolant cap on the left side of the engine bay.
Once I installed the new sensor in and put the D ring back on, screwed thermostat back into place.
Now my question is....what happened with the coolant leaking like that at the bottom of the car? Did the pressure build up too much everywhere? What should I do about it? Just refill the coolant? Or did I perhaps cause a rupture anywhere?
Removed D ring (without removing thermostat) and took out the old CTS. Quick spurt of coolant jumped out at me, nothing too bad.
Had a lot of trouble installing D ring back on with the new CTS - no clearance to put it back in.
Slightly loosened the thermostat so that I can have clearance to put the D ring back in. When I started tightening everything back up I started noticing that coolant was leaking at the bottom of the car. At this point i realized there was a lot of pressure somewhere so I unscrewed the coolant cap on the left side of the engine bay.
Once I installed the new sensor in and put the D ring back on, screwed thermostat back into place.
Now my question is....what happened with the coolant leaking like that at the bottom of the car? Did the pressure build up too much everywhere? What should I do about it? Just refill the coolant? Or did I perhaps cause a rupture anywhere?
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Joined: Dec 2002
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From: LA
W210 E320
Okay, I topped off with distilled water and have not noticed any leaking past couple days. Have not driven the car after fixing, will try and run the car this weekend.
Previous history (before swapping out Coolant Temperature Sensor) Regarding my CEL:
1. Has been on for a couple months and had no problem.
2. Engine shut off at stop sign one day but I was able to turn car off and restart with no problem.
3. 1 week later at a red light, engine died and would not turn back on. I could hear it trying to start but would not turn over. Had to push car to the safety lane and left it to cool down for a couple hours. Later that evening it started back up again. Could this be a CPS sensor failure also?
4. I tested the old Coolant temperature sensor for resistance and saw that it did lower resistance when in hot water. 2.2k when cold, and .9 in hot water. Not sure if theres a specific range it has to be at.
Previous history (before swapping out Coolant Temperature Sensor) Regarding my CEL:
1. Has been on for a couple months and had no problem.
2. Engine shut off at stop sign one day but I was able to turn car off and restart with no problem.
3. 1 week later at a red light, engine died and would not turn back on. I could hear it trying to start but would not turn over. Had to push car to the safety lane and left it to cool down for a couple hours. Later that evening it started back up again. Could this be a CPS sensor failure also?
4. I tested the old Coolant temperature sensor for resistance and saw that it did lower resistance when in hot water. 2.2k when cold, and .9 in hot water. Not sure if theres a specific range it has to be at.
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Your description of "warm-enginecut-off" with "restarts-when-engine-cold" - yes - is symptom of failing/failed CPS sensor - I am not a fan of the China knockoff/cheap part - recommend genuine Bosch (not retail auto parts store's claim "part-made by Bosch - which is bullsh*t.
Genuine Bosch from trusted source about $35-$40 - best to take out your existing CPS to determine if it is "one notch style" or "two notch style".
When you replaced the CTS - was that because you got a CEL code pointing to that specific part ?
Just trying to be of help - keep the beat !
Genuine Bosch from trusted source about $35-$40 - best to take out your existing CPS to determine if it is "one notch style" or "two notch style".
When you replaced the CTS - was that because you got a CEL code pointing to that specific part ?
Just trying to be of help - keep the beat !
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Joined: Dec 2002
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From: LA
W210 E320
Yes, I replaced CTS because of the error code P0115 - which relates to the CTS.
I guess the only way I can be sure if the CPS is also bad is if the car shuts down on me one more time? Perhaps I should replace it just to be safe beforehand. I wish it was not so hard to access.
Just drove the car around for a bit, cleared the CEL. It did not come back after replacing CTS. I made sure to stop at a lot of stop signs and the car did not die. However today the temperature is cool, on the day it would not start back up the weather was very warm, not sure if that also has an effect.
I guess the only way I can be sure if the CPS is also bad is if the car shuts down on me one more time? Perhaps I should replace it just to be safe beforehand. I wish it was not so hard to access.
Just drove the car around for a bit, cleared the CEL. It did not come back after replacing CTS. I made sure to stop at a lot of stop signs and the car did not die. However today the temperature is cool, on the day it would not start back up the weather was very warm, not sure if that also has an effect.
Last edited by Vamz; Jun 17, 2016 at 11:22 PM.
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Well, if CTS replacement corrected your PO115 - good news - "often" that code gets triggered by a partially open thermostat - and "often" that thermostat has malfunctioned because of sh*tty coolant mix for a aweful long time.
Your "engine-dies-warm-like-someone-turned-a-off-switch - if you want to wait till it happens again - to save $35-$40 now for a proper CPS replacement - have at it buddy !
Your "engine-dies-warm-like-someone-turned-a-off-switch - if you want to wait till it happens again - to save $35-$40 now for a proper CPS replacement - have at it buddy !
Thread Starter
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Joined: Dec 2002
Posts: 233
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From: LA
W210 E320
Well, if CTS replacement corrected your PO115 - good news - "often" that code gets triggered by a partially open thermostat - and "often" that thermostat has malfunctioned because of sh*tty coolant mix for a aweful long time.
Your "engine-dies-warm-like-someone-turned-a-off-switch - if you want to wait till it happens again - to save $35-$40 now for a proper CPS replacement - have at it buddy !
Your "engine-dies-warm-like-someone-turned-a-off-switch - if you want to wait till it happens again - to save $35-$40 now for a proper CPS replacement - have at it buddy !
Have not seen the CEL after replacing the CTS! I did suspect the thermostat also, however if the CEL comes on again then we will know it's status.
Could a partially open thermostat cause the engine to die at idle?
