CM2250 Poor fuel mileage

[Rawze]

(02-08-2022 )Truckdriven Wrote:  ...
As far as exhaust pressure reading I replaced the sensor and the tube and it seems to be reading properly at atmospheric pressure. The old tube was not clogged I could blow air through yet
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It is never usually the tube that clogs up, but the circuit thru the thermostat housing itself.
ref:

Quote:...
remove the sensor and plug it back into the harness ... spray moderate amount of brake cleaner into the hole where it mounts... crank truck to see if the brake cleaner comes blasting back up out of the hole.
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