Ford Escape Automobiles Forum banner
1 - 9 of 9 Posts

·
Registered
Joined
·
191 Posts
Discussion Starter · #1 ·
2002 Escape XLS 2.0L I-4 w 5-spd manual transmission.

Are there resistance values for the DPFE that can be checked?

Also, I found a voltage test procedure for it. Does "back probing" mean to insert the test probes where the wires go into the back side of the harness socket for the DPFE? If my test probes are too big to fit in there.... What to do? Thank you.
 

·
Registered
Joined
·
1,659 Posts
hurk said:
2002 Escape XLS 2.0L I-4 w 5-spd manual transmission.

Are there resistance values for the DPFE that can be checked?

Also, I found a voltage test procedure for it. Does "back probing" mean to insert the test probes where the wires go into the back side of the harness socket for the DPFE? If my test probes are too big to fit in there.... What to do? Thank you.
There's a certain output voltage with a certain amount of vacuum applied but you need a hand vacuum pump.

Yes, that's what back probing means. They sell special pin probes for that but some claim that a straightened out paper clip will work.
 

·
Registered
Joined
·
191 Posts
Discussion Starter · #3 ·
2002 Escape XLS 2.0L 4-cyl 5-spd manual transmission 69,400 miles.

Thank you. So I guess the resistance can't be simply checked?

The car is hesitating under brisk throttle & I was kinda checking this & that before taking it to a mechanic. I'd read a number of posts virtually identical to my problem, and the DPFE/EGR-valve was a common fix. If I feather the throttle, the car drives pretty good except for some slight hesitation here n there (but the ac needs to be off when accelerating).

A new Motorcraft sensor didn't fix the problem & I wanted to rule out a defective new DPFE. The EGR valve seems to be functioning - I checked it by sucking on the vacuum nipple - the plate moves. I don't know if this is a valid test, though. The orifices aren't clogged where they connect to the DPFE & EGR valve. Any comments or suggestion are greatly appreciated.
 

·
Registered
Joined
·
1,659 Posts
hurk said:
2002 Escape XLS 2.0L 4-cyl 5-spd manual transmission 69,400 miles.

Thank you. So I guess the resistance can't be simply checked?

The car is hesitating under brisk throttle & I was kinda checking this & that before taking it to a mechanic. I'd read a number of posts virtually identical to my problem, and the DPFE/EGR-valve was a common fix. If I feather the throttle, the car drives pretty good except for some slight hesitation here n there (but the ac needs to be off when accelerating).

A new Motorcraft sensor didn't fix the problem & I wanted to rule out a defective new DPFE. The EGR valve seems to be functioning - I checked it by sucking on the vacuum nipple - the plate moves. I don't know if this is a valid test, though. The orifices aren't clogged where they connect to the DPFE & EGR valve. Any comments or suggestion are greatly appreciated.
Yes, there isn't a resistance test. Pulling the EGR hose off at idle shouldn't affect the RPM at all and/or there shouldn't be any vacuum coming from that hose.

Years ago I had a '97 Ranger with a EGR issue. I had a vacuum gage connected to the EGR valve, a DMM monitoring the DPFE voltage and a scope on the EGR solenoid as it's a PWM signal. All that while shifting a 5-speed too!! I found that my EGR valve wasn't closing all the way at idle sometimes.
 

·
Registered
Joined
·
191 Posts
Discussion Starter · #5 ·
hee. sounds like you had your hands full.

There's no vacuum at the EGR hose at idle. I'll see if I can determine if the plate isn't seating properly (or whatever the thing is called that closes). The EGR valve is carbon fouled but it didn't look that bad.

The car is now 8 yrs old & it's nearing the 70k mark on the odo, so I've started doing some pre-emptive parts replacement, particularly in regards to the emissions system.
 

·
Registered
Joined
·
1,659 Posts
hurk said:
hee. sounds like you had your hands full.

There's no vacuum at the EGR hose at idle. I'll see if I can determine if the plate isn't seating properly (or whatever the thing is called that closes). The EGR valve is carbon fouled but it didn't look that bad.

The car is now 8 yrs old & it's nearing the 70k mark on the odo, so I've started doing some pre-emptive parts replacement, particularly in regards to the emissions system.
The DPFE output determines if there is or how much EGR flow there is. I don't remember if it's 0V at max flow or no flow! With a cheap hand vacuum pump, you can verify DPFE operation.

You could pull/plug the ERG hose and see if you still have your problem and that would eliminate the whole EGR system.
 

·
Registered
Joined
·
191 Posts
Discussion Starter · #7 ·
Thanks again. I found a couple of sensor troubleshooting posts w the specifics for the V6. I'm assuming the I-4 is similar.
I'll investigate stuff further today.
 

·
Registered
Joined
·
17 Posts
Now the DPFE sensor has 2 rubber hoses (about 3/8" dia) coming off the bottom leading in to 2 metal tubes which are leading into a 1" metal EGR pipe coming off the exhaust manifold. On the side of the sensor is a 3-wire connector. This assembly is the DPFE sensor.
Remove the 2 rubber hoses from the bottom of the sensor. Attach a piece of rubber hose to the forward most hole in the sensor. Now carefully take a small safety pin and stick it in behind the top wire parallel to the wire. You do NOT want to pierce the wire, only make contact inside the connector. This top wire is the active feedback signal wire. It will vary from 0-5 volts or so. The middle wire is ground. The bottom wire is 5-6 volts supply. Now the top wire voltage will vary as the pressure between the two holes in the sensor varies. Set your meter to read volts, either turn the key until the accessories are on or start the engine, either way is fine. Now using your mouth apply suction to the hose and you will see the voltage change from near 0 to near 5 if you apply enough suction. The vacuum on the hose should hold your tongue and not leak. If the voltage does not vary or is stuck high or low, the sensor is bad. Do the same thing to the rear port but the voltage difference will be much less, this is the reference port.
If the sensor seems to be working then you can further test the system by doing the following. Attach the hoses to the sensor as normal. Now remove the rubber vacuum hose from the top of the EGR valve diaphragm. With the truck running apply slight vacuum to the EGR valve and this will open the EGR valve. When the valve opens you will see the voltage on the top wire of the DPFE sensor change indicating flow. When the vacuum is applied your truck should stumble or almost stall indicating the EGR valve has opened which it normally does not do at idle. I hope this helps.
 

·
Registered
Joined
·
191 Posts
Discussion Starter · #9 ·
Yes, it does help. Actually, I may have read this procedure before.... maybe it was one of your posts. Thanks.
 
1 - 9 of 9 Posts
Top