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I am try to get my truck 100%. Using Forscan
I can read the engine coolant temp. It has been around 40* here. After the truck has been started
I am getting a reading of 20*. After full warm up
it will read in the low 40s. EOT is at 140-160.
Is this a bad sensor?. The high idle kicks on
when the dash gauge shows the truck is warm.
02 6 speed manual 4x4
Also I have been looking at threads. I have a sensor
behind the tensioner to the left on the water pump.
Is this the ECT sensor and what is the correct part number? From threads I have 3F1Z-12A648-A
Thanks
It doesn't sound like the sensor is bad. The PCM will command rev-up if the engine starts to cool when the truck is sitting still, even after the truck has been running around for awhile. 40 deg F ambient seems a little high for that to occur though.
Yes, I believe the sensor on the water pump is working properly. I am trying to figure if there is a 2nd sensor, its location and if it needs replaced.
I dont think the high idle should kick on after the engine is warm.
Yes, I believe the sensor on the water pump is working properly. I am trying to figure if there is a 2nd sensor, its location and if it needs replaced.
I dont think the high idle should kick on after the engine is warm.
Thanks for the pictures. I dont think I have a sensor in that location. I replaced the water pump
a year ago, right now I believe it only had one sensor going to the dash. I will check when I get home. While researching threads, I found post that show a sensor behind the belt tensioner. It is very difficult to get to, but I was able to confirm I have this sensor. I can touch it and I can see the wires running to it. On Forscan it is reading 20° but the temp outside is 40° On other post folks are saying it should be close to EOT.
Thanks for the reply
Also, went to the 2003 PCM wiring diagram and found the circuit that is for the ECT (MT) and TFT (AT) which I have indicated in a red box below. The wire colors should/might be ORG/BLK and GRY/RED.
If/when you confirm the location of the second sensor, please post here with confirmation and an image if possible. Not many of us have the ZF6 transmission, so the information on MT only items is a bit sparse. Any additional information you can provide would greatly appreciated.
That thread is how I found the what I think is the sensor, just wanted to confirm it. Thanks for the color combo. I will check that when I get back to the truck.
You are welcome sir, please post back with what you find and I wish you the best of luck. If needed, I can go out to my truck and verify what you are seeing. The sensor location should be the same on our trucks, but the wiring "might" be a different color because you have a 2002 and I have a 2000 and some of the wiring changed a bit between the MY of trucks.
Do you get a ECT temp reading from your scan tool.
If so, does it read close to the oil temp when cold?
Yes and yes. It has been years since I checked it via TP, but I remember ECT reading pretty close to EOT. This was when I was new to the 7.3L and was trying to figure out why my TFT was not reading properly. Well, the ZF6 does not have a TFT sensor to read, but it does have the ECT sensor to read. The early 99 and 99.5 ZF6 trucks do not have the ability to read ECT, but the 2000+ trucks like yours and mine should.
