95 windstar dpfe signal voltage
uzzo2
06-03-2007, 09:59 AM
i was recently given a 95 windstar 3.8l engine by my in-laws and from reading a lot of info on the net about them i know exactly how much they like me now. the check engine light is on, bought a code scanner and got 5 codes p1405, p1131, p1151, p0171, p0174. i checked the hoses on the dpfe sensor and sure enough one of them was off and the other was in the wrong place, fixed that and drove the van, the light came on again now it's showing 3 codes p1407, p0171, p0174. i read my repair manual about the sensor, said to take a meter and check the voltage on the sig/rf line with the ignition on and the voltage should be between .20 and .70 volts i'm only getting .06 volts, any ideas? also am wondering if the dpfe problem is contributing to the 0171 and 0174 codes. thanks in advance for any help
wiswind
06-03-2007, 06:29 PM
The P0171 & 174 are most likely cause by a vaccum leak.
Another possibility is the Mass Air Flow sensor (MAF), which I show how to clean in my pictures.
The DPFE should not cause the problem....unless it is giving out a crazy voltage that is causing the PCM to try to adjust to it....causing other issues......as in opening the EGR valve too much, too little, or cycling it too much....and the DPFE is a somewhat high failure item.
Double check the vaccume lines, including the one to the top of the EGR valve, and the one from the EGR valve to the intake manifold, as well as the crankcase breather line that goes from the front valve cover, to the air intake hose. These, as well as a number of other vaccum lines can become cracked, disconnected, etc, causing too much air, which the computer does not know about, to enter the intake.....causing the lean codes.
Another possibility is the Mass Air Flow sensor (MAF), which I show how to clean in my pictures.
The DPFE should not cause the problem....unless it is giving out a crazy voltage that is causing the PCM to try to adjust to it....causing other issues......as in opening the EGR valve too much, too little, or cycling it too much....and the DPFE is a somewhat high failure item.
Double check the vaccume lines, including the one to the top of the EGR valve, and the one from the EGR valve to the intake manifold, as well as the crankcase breather line that goes from the front valve cover, to the air intake hose. These, as well as a number of other vaccum lines can become cracked, disconnected, etc, causing too much air, which the computer does not know about, to enter the intake.....causing the lean codes.
uzzo2
06-03-2007, 07:17 PM
The P0171 & 174 are most likely cause by a vaccum leak.
Another possibility is the Mass Air Flow sensor (MAF), which I show how to clean in my pictures.
The DPFE should not cause the problem....unless it is giving out a crazy voltage that is causing the PCM to try to adjust to it....causing other issues......as in opening the EGR valve too much, too little, or cycling it too much....and the DPFE is a somewhat high failure item.
Double check the vaccume lines, including the one to the top of the EGR valve, and the one from the EGR valve to the intake manifold, as well as the crankcase breather line that goes from the front valve cover, to the air intake hose. These, as well as a number of other vaccum lines can become cracked, disconnected, etc, causing too much air, which the computer does not know about, to enter the intake.....causing the lean codes.
thanks for the reply, what about the voltage on the sig/rf line the manual says it it should be between .20 and .60 volts, i'm only getting .05 volts, i can't imagine a vacuum leak the engine only has about 15k on it from jasper. but on the other hand it is leaking oil from the rear mail seal, don't know how you screw up putting a rear main seal on a new engine out of frame
Another possibility is the Mass Air Flow sensor (MAF), which I show how to clean in my pictures.
The DPFE should not cause the problem....unless it is giving out a crazy voltage that is causing the PCM to try to adjust to it....causing other issues......as in opening the EGR valve too much, too little, or cycling it too much....and the DPFE is a somewhat high failure item.
Double check the vaccume lines, including the one to the top of the EGR valve, and the one from the EGR valve to the intake manifold, as well as the crankcase breather line that goes from the front valve cover, to the air intake hose. These, as well as a number of other vaccum lines can become cracked, disconnected, etc, causing too much air, which the computer does not know about, to enter the intake.....causing the lean codes.
thanks for the reply, what about the voltage on the sig/rf line the manual says it it should be between .20 and .60 volts, i'm only getting .05 volts, i can't imagine a vacuum leak the engine only has about 15k on it from jasper. but on the other hand it is leaking oil from the rear mail seal, don't know how you screw up putting a rear main seal on a new engine out of frame
wiswind
06-03-2007, 07:38 PM
I would verify that the leak is engine oil, and not transmission fluid, as either one can leak at that point.
CLEAN transmission fluid will be red.
Also, a vaccum leak could develop due to the installation of the engine, as the 12 year old vaccum lines, etc, where moved about.
If you are not getting the voltage that you need at the DPFE, I would replace it......and, as you most likely have done, verify the condition of the hoses.
If you are getting an engine miss.....it could be a dirty fuel injector....as I have had both misfire codes and lean codes come up from that......as the PCM is trying to compensate for the misfire.
For an injector cleaning, I was directed to Berryman's B-12 Chemtool by my mechanic....and I had used a few other brands before that.
The Berryman's DOES work.
You can get it at Autozone, Advance Auto Parts, and a number of other places.
CLEAN transmission fluid will be red.
Also, a vaccum leak could develop due to the installation of the engine, as the 12 year old vaccum lines, etc, where moved about.
If you are not getting the voltage that you need at the DPFE, I would replace it......and, as you most likely have done, verify the condition of the hoses.
If you are getting an engine miss.....it could be a dirty fuel injector....as I have had both misfire codes and lean codes come up from that......as the PCM is trying to compensate for the misfire.
For an injector cleaning, I was directed to Berryman's B-12 Chemtool by my mechanic....and I had used a few other brands before that.
The Berryman's DOES work.
You can get it at Autozone, Advance Auto Parts, and a number of other places.
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