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cvar
Member
- Joined
- Apr 27, 2012
- Messages
- 588
- Reaction score
- 19
- Points
- 18
- Vehicle Year
- 1997
- Make / Model
- Mazda
- Engine Size
- 4.0L V6
- Transmission
- Automatic
My '97 4.0 OHV throws p1401 = EGR EVP Sensor Circuit High Voltage Detected.
If I clear the codes, it comes back immediately. It runs rough only between 30-40 mph. The CEL stays off.
Everything seems to test fine. DPFE signal is 1v at idle, rises up to 5V when I induce EGR, and engine stalls at idle when I induce EGR by activating (ie, ground) the EGR solenoid. DPFE signal seems OK, and not over 5V. So what am I overlooking?
Any ideas how to fix? I don't really want to replace all EGR, DPFE, hoses, and EGR orifice tube, when only 1 is faulty. But which one?
State inspection is almost due. My DPFE is 2 yrs old. I tested DPFE signal with voltmeter, as described in this video:
If I clear the codes, it comes back immediately. It runs rough only between 30-40 mph. The CEL stays off.
Everything seems to test fine. DPFE signal is 1v at idle, rises up to 5V when I induce EGR, and engine stalls at idle when I induce EGR by activating (ie, ground) the EGR solenoid. DPFE signal seems OK, and not over 5V. So what am I overlooking?
Any ideas how to fix? I don't really want to replace all EGR, DPFE, hoses, and EGR orifice tube, when only 1 is faulty. But which one?
State inspection is almost due. My DPFE is 2 yrs old. I tested DPFE signal with voltmeter, as described in this video:
