cusingeorge
Member
- Joined
- December 23, 2008
- Messages
- 12
- Reaction score
- 0
- City, State
- Calumet, Oklahoma
- Year, Model & Trim Level
- 97 Sport and 07 Limited
My 1997 4.0 SOHC 4X4 Sport Automatic (140,000 miles) misfired and the CEL came on. I drove it to Autozone and they put a code reader on and it gave these codes:
PO171
PO0300
Mileage went from ~19-20 to 11.5 mpg.
I can't really tell that it has lost any performance.
This started in Ocotober of 2007, since then I have had the injectors cleaned, replaced the plugs, wires, all the 02 sensors, air filter, fuel filter (2X), and have ran at least 2 cans of BG through it. I change the oil every 3000 miles and use a Motorcraft filter (FL1A) and Valvoline 5W30.
It has new Yokohama tires and all are at 32 psi.
I recently replaced the water pump, and thus all the coolant.
The brakes aren't dragging.
Here's what I'm thinking, please add or detract from this list:
1) Check my RPM's at 70 MPH (should be ~2200?)
2) Clean TB
3) Change Fuel Filter (again)
4) Clean MAF
5) Use SeaFoam instead of BG
6) Check the Fuel Pressure Regulator for leaks
7) Check the coolant temperature switch
8) Replace the catalytic converters
9) Replace the tranny fluid
I have heard about ethanol-based fuel breaking loose stuff that regular unleaded has deposited in the tank and lines, could this be the culprit?
Other ideas?
PO171
PO0300
Mileage went from ~19-20 to 11.5 mpg.
I can't really tell that it has lost any performance.
This started in Ocotober of 2007, since then I have had the injectors cleaned, replaced the plugs, wires, all the 02 sensors, air filter, fuel filter (2X), and have ran at least 2 cans of BG through it. I change the oil every 3000 miles and use a Motorcraft filter (FL1A) and Valvoline 5W30.
It has new Yokohama tires and all are at 32 psi.
I recently replaced the water pump, and thus all the coolant.
The brakes aren't dragging.
Here's what I'm thinking, please add or detract from this list:
1) Check my RPM's at 70 MPH (should be ~2200?)
2) Clean TB
3) Change Fuel Filter (again)
4) Clean MAF
5) Use SeaFoam instead of BG
6) Check the Fuel Pressure Regulator for leaks
7) Check the coolant temperature switch
8) Replace the catalytic converters
9) Replace the tranny fluid
I have heard about ethanol-based fuel breaking loose stuff that regular unleaded has deposited in the tank and lines, could this be the culprit?
Other ideas?