I had my truck bulletproofed in January. As soon as the weather warmed up the first of April I noticed my eot was running high while pulling a trailer. It got to 250 at one point but run steady at 230-240 which is still high. My ect was running 170's because the thermostat was stuck open. Changed it now it's running 188-192 as it should but the eot is running 220-230 after it heats up with equally with the ect. Has a new ford oil cooler with egr delete. Is it stopped up or do I have another problem? It did this within 2 months. Can I flush the system? I just now got enough miles for an oil change. Would new oil help? Th e mechanic wants to charge me labor to replace the part that is under warranty. It went out within 2 months.

 

I'd say your cooler is clogged again. Did you do a chemical flush before replacing it? Flushing is probably not going to help at this point, but if your running at 230-240 normally and 250 towing, I'd be thinking of doing a correct flush and a new cooler.

At EOT of 253 the engine will start to de-fuel to cool itself. Because you have a delete, the real temp is 253, that's the number to watch for and your close. ECT is fine at 188-192 and normal driving at EOT of 230, truck will run the fan hard.

 

The guy that did the work is a mechanic at a ford dealership. They tore it down to do the head studs. He should have flushed it. Don't think there was much left to flush.

 

He should have flushed it BEFORE the tear down. All the stuff that clogs coolers is very small as a cooler is a better filter than anything else. All that junk in the radiator, inside the block, heater core and..... you get the idea.

Like I said, 253 is your new number because of the deleted EGR, but running at 250 towing is very close to defuel and that oil sensor is probably not getting the real oil number for temps, it's much higher deep inside the motor.