Water in the DPFE Sensor '96 Ford Ranger 3.0L

DPFE was reporting a P0401 code and replaced it and ran for a couple of months w/o the code but then one morning it came back on. Drove it for months until I had time and warmer weather, when I pulled it off, I found water drops out which I could imagine would be the cause off the insufficient airflow code from the sensor. Took the water out and put back the same sensor, of course the code came back after a week. Checking there was water back in there again - glad I didn’t put a new sensor in. Where do you think the water comes from? I drive 20-40 miles and make it to 60mph at least a quarter of the time - I’ve read short trips can cause condensation but I’m about 10 miles from anything.

BTW - I just change the hoses to the sensor with those nice looking ones with the red liner - much tighter fit than the hoses that I replaced the last time. At the truck’s old age, it could be anything I suppose. I have a new DPFE sensor sitting in the box but don’t want to put it in until the water issue is resolved, …unfortunately the truck needs to pass inspection within the month.
96’ Ranger 6cyl3.0l 180k great truck.
Thanks for your time and any feedback.

The moisture in the DPFE sensor is caused by the exhaust gasses. Moisture is one of the by-products of combustion.

The DPFE sensor measures the Delta P at the orifice located inside the pipe from the exhaust pipe to the EGR valve. The moisture is forced into DPFE sensor in the high side pressure hose to the DPFE sensor.

One way to prevent moisture from getting into DPFE sensor is, purchase a desiccant filter that’s used on the air inlet port of a paint gun. Install the desiccant filter in the high side pressure hose between the EGR pipe and DPFE sensor where it can be monitored. Then when the desiccant changes color because of the moisture, just replace the desiccant.



Check this out. Skip to page 26


Seems to me the code is for EGR flow. That being the case, perhaps the problem isn’t the sensor or the hose, but the EGR valve itself, or the EGR passages

Activate the EGR if you’re able to . . . with a scan tool, for example

Does the engine stall, or at least run very badly?