Fan Clutch control parameters
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Tuned
Joined: Aug 2003
Posts: 285
Likes: 5
From: Mena, AR
Fan Clutch control parameters
I've got a 6.4 (fully deleted) with a fan clutch issue. The fan is running far more than it should and I want to know which temp sensors the PCM uses to adjust the fan speed. I've looked at my coolant and engine oil temp and both are running about 190-195 for coolant and oil temp about 5-7 degrees above the coolant, which I believe is normal. I can turn off the HVAC and it still roars like a big rig even when there seems to be no need. Even on cool mornings the fan clutch engages and it seems to run far too much. My fuel mileage is suffering and I'm about to take a weekend trip. I don't want that thing roaring on the highway at 70+ MPH speeds. All of my driving is pretty normal with no trailer loads. Ambient temps don't seem to be a factor but we are in the mid 90's with high humidity. My intake air temp also seems to be reading correctly. Just not sure what's triggering the PCM to engage the fan.
Thanks!
Thanks!
Thread Starter
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Tuned
Joined: Aug 2003
Posts: 285
Likes: 5
From: Mena, AR
Checked my fuel rail temp at hot idle and was 171. So, I bet the sensor is bad or the little coolant pump on the fuel cooler is bad. I changed the hoses on the cooler a while back because they get pinched and leak. May have air in there as well. Seems like most are saying that the temp should be no more than 30 degrees above ambient if under no large load.
Mountain Pass
Joined: Aug 2021
Posts: 142
Likes: 14
I've got a 6.4 (fully deleted) with a fan clutch issue. The fan is running far more than it should and I want to know which temp sensors the PCM uses to adjust the fan speed. I've looked at my coolant and engine oil temp and both are running about 190-195 for coolant and oil temp about 5-7 degrees above the coolant, which I believe is normal. I can turn off the HVAC and it still roars like a big rig even when there seems to be no need. Even on cool mornings the fan clutch engages and it seems to run far too much. My fuel mileage is suffering and I'm about to take a weekend trip. I don't want that thing roaring on the highway at 70+ MPH speeds. All of my driving is pretty normal with no trailer loads. Ambient temps don't seem to be a factor but we are in the mid 90's with high humidity. My intake air temp also seems to be reading correctly. Just not sure what's triggering the PCM to engage the fan.
Thanks!
Thanks!
Checked my fuel rail temp at hot idle and was 171. So, I bet the sensor is bad or the little coolant pump on the fuel cooler is bad. I changed the hoses on the cooler a while back because they get pinched and leak. May have air in there as well. Seems like most are saying that the temp should be no more than 30 degrees above ambient if under no large load.
This is from the Ford Manual for Clutch control Parameters.
Thread Starter
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Tuned
Joined: Aug 2003
Posts: 285
Likes: 5
From: Mena, AR
Thanks
Thanks for the fan clutch inputs. Pretty certain it’s the fuel temp causing the fan to operate a lot more than usual. Mine is 170 degrees at idle. Pulling fuel coolant pump tomorrow morning to check operation and will also change fuel temp sensor. I have a 6 hour trip this weekend. Not sure how much damage this will cause if I cant get it repaired/replaced in time. Nobody locally has the pump.
Mountain Pass
Joined: Aug 2021
Posts: 142
Likes: 14
Thanks for the fan clutch inputs. Pretty certain it’s the fuel temp causing the fan to operate a lot more than usual. Mine is 170 degrees at idle. Pulling fuel coolant pump tomorrow morning to check operation and will also change fuel temp sensor. I have a 6 hour trip this weekend. Not sure how much damage this will cause if I cant get it repaired/replaced in time. Nobody locally has the pump.
Whats the Sensor reading on a cold soak?
Mountain Pass
Joined: Aug 2021
Posts: 142
Likes: 14
Thanks for the fan clutch inputs. Pretty certain it’s the fuel temp causing the fan to operate a lot more than usual. Mine is 170 degrees at idle. Pulling fuel coolant pump tomorrow morning to check operation and will also change fuel temp sensor. I have a 6 hour trip this weekend. Not sure how much damage this will cause if I cant get it repaired/replaced in time. Nobody locally has the pump.
Thread Starter
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Tuned
Joined: Aug 2003
Posts: 285
Likes: 5
From: Mena, AR
Cold soak of 14 hours (with ambient temp of 82 outside) and I'm reading 92 degrees so it doesn't seem too far off. Oddly, with KOEO, I hear a high pitched whine just over the EGR valve. I think that's a new noise not heard before. I'll check the pump cooler next to see if it's running. I don't think it is.
Thanks for all of the help.
Thanks for all of the help.
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Thread Starter
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Tuned
Joined: Aug 2003
Posts: 285
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From: Mena, AR
Fuel coolant pump is faulty. Pulled and put 12 to it and it starts but then stops. Have to spin it to get it to start again. Off to find a part within 100 miles of me. Yippee!
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Thread Starter
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Tuned
Joined: Aug 2003
Posts: 285
Likes: 5
From: Mena, AR
Changed out fuel coolant pump and bled air from system. Fan still runs more than expected but seems to have come down a bit. My fuel temp has dropped to 120's from 170. Engine coolant is 195 but now my oil temp is 215 running down the road at 40 MPH with very little load. I wish I had a good real time monitor for all of the sensors. All I have is AutoEnginuity running from the laptop and that's not very reliable. Anyone have a good monitoring system to reccomend?
Mountain Pass
Joined: Aug 2021
Posts: 142
Likes: 14
Changed out fuel coolant pump and bled air from system. Fan still runs more than expected but seems to have come down a bit. My fuel temp has dropped to 120's from 170. Engine coolant is 195 but now my oil temp is 215 running down the road at 40 MPH with very little load. I wish I had a good real time monitor for all of the sensors. All I have is AutoEnginuity running from the laptop and that's not very reliable. Anyone have a good monitoring system to reccomend?
For A laptop Forscan is the best money-wise, last time I subscribed for 3 years it was $50. Can read almost all PIDs, do Self-Preformance Tests, Injector Disable, RPM Control, Etc.
Thread Starter
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Tuned
Joined: Aug 2003
Posts: 285
Likes: 5
From: Mena, AR
Just a quick update to the fan saga. Started out for a weekend trip pulling a small 6x9 trailer and made it 2 hours from home before the transmission started to act up. Threw a P2701 and P0756 code and also got the dreaded wrench symbol. The transmission is having trouble shifting into high gear at highway speeds. Also, the upshift from 2-3 is rough. Made it back home without too much trouble but now it's time to look into the transmission. I hope it's just solenoid issues. The fan was quiet for the first 2 hours of the trip and then began ramping up and down just the same as before at 70 MPH speeds. Forscan module arrives Thursday so that I can watch my temps a little easier. I'm fairly certain an oil cooler changeout is in my very near future.
Mountain Pass
Joined: Aug 2021
Posts: 142
Likes: 14
Just a quick update to the fan saga. Started out for a weekend trip pulling a small 6x9 trailer and made it 2 hours from home before the transmission started to act up. Threw a P2701 and P0756 code and also got the dreaded wrench symbol. The transmission is having trouble shifting into high gear at highway speeds. Also, the upshift from 2-3 is rough. Made it back home without too much trouble but now it's time to look into the transmission. I hope it's just solenoid issues. The fan was quiet for the first 2 hours of the trip and then began ramping up and down just the same as before at 70 MPH speeds. Forscan module arrives Thursday so that I can watch my temps a little easier. I'm fairly certain an oil cooler changeout is in my very near future.
Have you checked your transmission fluid level and what condition it is in?
When did the Wrench light come on while driving, after the fan started kicking on or before?
Mountain Pass
Joined: Aug 2021
Posts: 142
Likes: 14
Just a quick update to the fan saga. Started out for a weekend trip pulling a small 6x9 trailer and made it 2 hours from home before the transmission started to act up. Threw a P2701 and P0756 code and also got the dreaded wrench symbol. The transmission is having trouble shifting into high gear at highway speeds. Also, the upshift from 2-3 is rough. Made it back home without too much trouble but now it's time to look into the transmission. I hope it's just solenoid issues. The fan was quiet for the first 2 hours of the trip and then began ramping up and down just the same as before at 70 MPH speeds. Forscan module arrives Thursday so that I can watch my temps a little easier. I'm fairly certain an oil cooler changeout is in my very near future.
If I remember right l certain transmission codes will set the wrench light.
Thread Starter
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Tuned
Joined: Aug 2003
Posts: 285
Likes: 5
From: Mena, AR
No limp mode
Did not go into reduced power. I did reset the codes after taking a snapshot and then very gingerly got back on the highway and made it home without too much trouble. The transmission is definitely not acting right. Upshift from 2-3 is rough and it does hesitate to go into final gear. The fan cycled continually for 2 hours. Ramped up to full and gradually ramped down to nothing and then 5 seconds later it repeated the cycle.
Mountain Pass
Joined: Aug 2021
Posts: 142
Likes: 14
Did not go into reduced power. I did reset the codes after taking a snapshot and then very gingerly got back on the highway and made it home without too much trouble. The transmission is definitely not acting right. Upshift from 2-3 is rough and it does hesitate to go into final gear. The fan cycled continually for 2 hours. Ramped up to full and gradually ramped down to nothing and then 5 seconds later it repeated the cycle.
How is your transmission fluid?