99 Cougar P0174,P0442,P1744
dmann120
05-04-2009, 11:45 PM
My 99 Cougar V6 had the following codes, P0174,P0442, EGR flow issue and the dreaded P1744 for the lock up torque converter.
EGR flow issues, try cleaning the EGR port behind the throttle body and TB gasket. There is a port that leads to the EGR valve. If you have a lot of miles on the vehicle, it is most likely clogged with carbon. Use a soft metal wire and carb cleaner to remove the carbon and open a path through the EGR Port. I found out the hard way and purchased a new EGR valve, DPFE sensor and Vacuum Regulator....money well spent because the car was used...yet the old parts were probably good.
P0174 Lean Condition Bank 2 and P0442 Minor leak emission system. I installed new gaskets on the upper and lower intake manifold, cleaned the carbon from the assembly, the codes cleared. One additional code that has cleared is the P1744 Torque Converter Lockup clutch. I am still waiting for the CEL to return with that issue. The last test drive increased the fuel economy to 30 MPG according to the onboard computer, I would say it is about 27 MPG real world and that is still an improvement over 22 MPG. One thing I would suggest when changing the intake gaskets, clean the gunk from the six small butterfly valves under the intake plenum and use a shop vacuum to suck out the carbon flakes, carb cleaner and debris from the 12 ports.
EGR flow issues, try cleaning the EGR port behind the throttle body and TB gasket. There is a port that leads to the EGR valve. If you have a lot of miles on the vehicle, it is most likely clogged with carbon. Use a soft metal wire and carb cleaner to remove the carbon and open a path through the EGR Port. I found out the hard way and purchased a new EGR valve, DPFE sensor and Vacuum Regulator....money well spent because the car was used...yet the old parts were probably good.
P0174 Lean Condition Bank 2 and P0442 Minor leak emission system. I installed new gaskets on the upper and lower intake manifold, cleaned the carbon from the assembly, the codes cleared. One additional code that has cleared is the P1744 Torque Converter Lockup clutch. I am still waiting for the CEL to return with that issue. The last test drive increased the fuel economy to 30 MPG according to the onboard computer, I would say it is about 27 MPG real world and that is still an improvement over 22 MPG. One thing I would suggest when changing the intake gaskets, clean the gunk from the six small butterfly valves under the intake plenum and use a shop vacuum to suck out the carbon flakes, carb cleaner and debris from the 12 ports.
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