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CHT - older vs newer models?

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Location
Northern Virginia
#1
Trying to install a 2018 FiST motor in a 2015 FiST.

The old motor appears to have a cylinder head temperature sensor … the new motor does not.

Did the new motors forgo those sensors entirely? If so, can I have this accounted for in the tune?
 


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OP
cidsamuth
Messages
318
Likes
323
Location
Northern Virginia
Thread Starter #3
That's probably the sensor installed in the recall beccause the head problem on the 2014 and 2015 cars. They fixed the head problem on the 2016 and up cars so they don't need the recall parts.
That would imply they put a new head on during the recall, inclusive of a new wiring harness …. I don’t think the recall was that extensive, was it?

To my knowledge, the recall was for a coolant LEVEL sensor only.

Besides, I don’t think the recall was ever even done on my car, as the reservoir is not the right shape.
 


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Cape Town
#4
That would imply they put a new head on during the recall, inclusive of a new wiring harness …. I don’t think the recall was that extensive, was it?

To my knowledge, the recall was for a coolant LEVEL sensor only.

Besides, I don’t think the recall was ever even done on my car, as the reservoir is not the right shape.
Did you ever confirm this?
I think you are right, the recall added the new coolant lines, coolant level sensor, replacement thermostat, bypass valve, and some odds and ends. The programming added ECU logic to protect the cylinder head in case of low coolant levels and additional warning messages on the dash.

The newer cars had a different cylinder head design, which probably moved or completely negated the need for the sensor (head temp is probably calculated and not measured directly). Try to get the newer factory calibrations flashed to your old ECU if possible to confirm thing are working as expected.
 


OP
cidsamuth
Messages
318
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323
Location
Northern Virginia
Thread Starter #5
Did you ever confirm this?
I think you are right, the recall added the new coolant lines, coolant level sensor, replacement thermostat, bypass valve, and some odds and ends. The programming added ECU logic to protect the cylinder head in case of low coolant levels and additional warning messages on the dash.

The newer cars had a different cylinder head design, which probably moved or completely negated the need for the sensor (head temp is probably calculated and not measured directly). Try to get the newer factory calibrations flashed to your old ECU if possible to confirm thing are working as expected.
You're on the money, reference the recall and the revised head in later years (but not as part of the recall).

As for the sensor, turns out that I likely got a 1.6 Escape motor, which I guess didn't have the same sensor. The motor has since been switched out with a correct one from a FiST.
 


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