MA Ranger
Member
- Joined
- May 19, 2009
- Messages
- 49
- Reaction score
- 0
- Points
- 6
- Vehicle Year
- 1994
- Make / Model
- Ford
- Transmission
- Automatic
My check engine light (CEL) is on continuously in my '94 Ranger 3.0L. I conducted a KOEO test with a scanner and it showed code 337 (EGR Valve Pressure Transducer/Position Sensor circuit above maximum voltage). I replaced the DPFE sensor with an aftermarket "metallic" one I bought at a parts store (the old one that was on the truck was the same kind), but the CEL is still on and the KOEO scan still shows code 337.
I tested the DPFE sensors (both new and old) and connector with a multi-meter and got the following results:
Back-probe brown/light green wire (top of connector):
4.95 volts old sensor/4.98 volts new when connected to the DPFE sensor
0.07 volts when disconnected
Tested grey/red wire (middle of connector) for ground (with test lamp): good
Tested brown/white wire (bottom of connector) when disconnected to the DPFE sensor: 5.0 volts
I tested the EGR valve with a vacuum pump and it tested normal (engine stalled when gage on the pump showed 15 - 17)
Other than the CEL on all the time, the engine runs normal - not overheating, idle is o.k. and it runs normal under all operating conditions (no change in performance before and after the CEL coming on). The only time the CEL turned off was when I was driving home from work today - it went off for about 10 seconds after I hit a bump in the road. Other than that, it's been on for about a month now.
I suspect that the new DPFE sensor might be bad too, but I'm not sure and it seems odd that it would be bad right out of the box. Any help would be greatly appreciated.
I tested the DPFE sensors (both new and old) and connector with a multi-meter and got the following results:
Back-probe brown/light green wire (top of connector):
4.95 volts old sensor/4.98 volts new when connected to the DPFE sensor
0.07 volts when disconnected
Tested grey/red wire (middle of connector) for ground (with test lamp): good
Tested brown/white wire (bottom of connector) when disconnected to the DPFE sensor: 5.0 volts
I tested the EGR valve with a vacuum pump and it tested normal (engine stalled when gage on the pump showed 15 - 17)
Other than the CEL on all the time, the engine runs normal - not overheating, idle is o.k. and it runs normal under all operating conditions (no change in performance before and after the CEL coming on). The only time the CEL turned off was when I was driving home from work today - it went off for about 10 seconds after I hit a bump in the road. Other than that, it's been on for about a month now.
I suspect that the new DPFE sensor might be bad too, but I'm not sure and it seems odd that it would be bad right out of the box. Any help would be greatly appreciated.
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