- Location
- Roanoke VA
I ask because my 94 with a 96 4.0 and new timing chain gets terrible fuel economy. Its bone stock getting 10mpg
I have tried everything, replaced everything. Here is the list of new parts;
NGK O2
Champion plugs
CTS
MAT
MAP
injectors
FPR
Bosch fuel pump(old one died)
Accel cap, wires, rotor
Catyletic converter
Things I have tried;
I borrowed a known good ECU from a friends 94 XJ that gets normal mileage-no change.
Cleaned all connections and grounds-no change.
Using the GPS to check mileage between fill ups(the odometer is correct though)-results were the same.
Checked for vacuum leaks-none
Cleaned the TB and intake(I cleaned the intake in a ultrasonic cleaner)-no change.
Checked the brakes and axles for any parasitic drag-nothing.
Lastly, and why I ask, would a timing chain cause poor fuel economy? I installed a new chain set before I dropped the motor in and while I was replacing all of the seals and gaskets. I guess its possible that I got it off a tooth but I have done a good many with no issues. I have tried everything else so now I'm doubting myself.
The Jeep runs better than the other three in my driveway.
I am about to give up on it.
I have tried everything, replaced everything. Here is the list of new parts;
NGK O2
Champion plugs
CTS
MAT
MAP
injectors
FPR
Bosch fuel pump(old one died)
Accel cap, wires, rotor
Catyletic converter
Things I have tried;
I borrowed a known good ECU from a friends 94 XJ that gets normal mileage-no change.
Cleaned all connections and grounds-no change.
Using the GPS to check mileage between fill ups(the odometer is correct though)-results were the same.
Checked for vacuum leaks-none
Cleaned the TB and intake(I cleaned the intake in a ultrasonic cleaner)-no change.
Checked the brakes and axles for any parasitic drag-nothing.
Lastly, and why I ask, would a timing chain cause poor fuel economy? I installed a new chain set before I dropped the motor in and while I was replacing all of the seals and gaskets. I guess its possible that I got it off a tooth but I have done a good many with no issues. I have tried everything else so now I'm doubting myself.
The Jeep runs better than the other three in my driveway.
I am about to give up on it.
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