DPFE help
#1
01-14-2011, 09:50 PM
DPFE help
I am new so please break everything down Barney style. I have a 1997 150 xlt extended cab with about 175,000 miles that I bought a couple years ago after I got back from Iraq. This is not my primary vehicle and rarely use it. My first problem is that my DPFE sensor or plug that plugs into it does not stay attached. Can someone please tell me if this is a big problem and if it is easy to replace. The sensor is in place but the plug is the one that will not stay plugged in. Not sure if this is related but when I turn my truck off I hear a hissing/humming from around the DPFE area. Can someone please tell me if either of these problems are common in this model?
I also must have a slow electrical drain, my truck dies in about a week if I leave the negative connected. Would any of the issues above affect my battery? Thanks for any assistance anyone could give me.
I also must have a slow electrical drain, my truck dies in about a week if I leave the negative connected. Would any of the issues above affect my battery? Thanks for any assistance anyone could give me.
#2
01-15-2011, 01:57 AM
Hello 'Barney',
Thank you for your service to our country.
If you have no code or drivability issue with the plug in place, the plug lock must be broken at some place. I would look at using a tie wrap to hold it in place.
As for the noise, my guess is the EGR vacuum regulator may be sticking. What it does under control of the computer, allows intake vacuum to pass to the EGR valve opening it up. The EGR must have outside air allowed back in for it to close again.
The EGR valve 'regulator' is a 3 port device meaning it lets air back into the feed hose to the EGR when not operated. If the EGR is held open it tries to get air so could make the noise as it slowly draws air from some place letting it slowly leak into the EGR.
The EGR has a spring loaded rubber diaphram that pulls a pintel valve open to let some exhaust gas flow from the exhaust manifold back into the intake.
I would do two things. Clean the vacuum regulator and it's sponge filter under the cap to make sure it is clean and does not stick closed , open or slow to operate.
If it clears the noise issue fine, if not , test the EGR for sticking open using a vacuum source to open it then to see if it stays open when the hose is blocked , then closes when suddenly opened. You should be able to hear this happen. If using a hand vac pump don't pump over about 15 inches of vacuum or you may wreck the EGR.
.
Electrical drain:
My bet is either you have something left powered on or the alternator does not disconnect after engine shutdown.
To rough test this, you can run to fully charge the battery, then remove the heavey lead at the alternator insulating it from grounding and see if the motor will crank after the usual interval. Notice if the heavey lead results in a noticable spark if touched back onto the alternator terminal.
If yes the alternator needs to be tested or replaced.
It is not supposed to drain any current at rest.
If you go this far, complete the charge system testing with a voltmeter to be sure the repaired system is charging properly by observing the voltage rise just after cranking and running.
Expect the voltage to rise to about 15.5 volts +/- then slowly drop back to about 14 volts as the battery recovers from the drain of starting.
How fast it recovers is a function of the charge voltage rise and the health of the battery to accept the recharge. If the battery seems not to recover within less than 10 minutes of running, have it's capacity tested and review the alternator's ability to raise it's voltage to replace the charge.
Note that the difference between the alternator voltage and the battery's voltage is what forces current to flow back into the battery for recharge. (15.5v minus 14v = 1.5 volts) this forces many amperes of current to flow toward the battery.
If either one or both has an issue, the recharge won't be satisfctory and you will be left with poor starting or no start.
As well, a faulty battery with one faulty cell cannot be recharged so the alternator keep trying to do it (alternator regulator does not know the battery is faulty) causing the battery to lose it's water in that cell first and causing more wear on the alternator.
You can begin to see the relationship of these system actions when good and bad.
Hope this covers most of it and is helpful.
Good luck.
Thank you for your service to our country.
If you have no code or drivability issue with the plug in place, the plug lock must be broken at some place. I would look at using a tie wrap to hold it in place.
As for the noise, my guess is the EGR vacuum regulator may be sticking. What it does under control of the computer, allows intake vacuum to pass to the EGR valve opening it up. The EGR must have outside air allowed back in for it to close again.
The EGR valve 'regulator' is a 3 port device meaning it lets air back into the feed hose to the EGR when not operated. If the EGR is held open it tries to get air so could make the noise as it slowly draws air from some place letting it slowly leak into the EGR.
The EGR has a spring loaded rubber diaphram that pulls a pintel valve open to let some exhaust gas flow from the exhaust manifold back into the intake.
I would do two things. Clean the vacuum regulator and it's sponge filter under the cap to make sure it is clean and does not stick closed , open or slow to operate.
If it clears the noise issue fine, if not , test the EGR for sticking open using a vacuum source to open it then to see if it stays open when the hose is blocked , then closes when suddenly opened. You should be able to hear this happen. If using a hand vac pump don't pump over about 15 inches of vacuum or you may wreck the EGR.
.
Electrical drain:
My bet is either you have something left powered on or the alternator does not disconnect after engine shutdown.
To rough test this, you can run to fully charge the battery, then remove the heavey lead at the alternator insulating it from grounding and see if the motor will crank after the usual interval. Notice if the heavey lead results in a noticable spark if touched back onto the alternator terminal.
If yes the alternator needs to be tested or replaced.
It is not supposed to drain any current at rest.
If you go this far, complete the charge system testing with a voltmeter to be sure the repaired system is charging properly by observing the voltage rise just after cranking and running.
Expect the voltage to rise to about 15.5 volts +/- then slowly drop back to about 14 volts as the battery recovers from the drain of starting.
How fast it recovers is a function of the charge voltage rise and the health of the battery to accept the recharge. If the battery seems not to recover within less than 10 minutes of running, have it's capacity tested and review the alternator's ability to raise it's voltage to replace the charge.
Note that the difference between the alternator voltage and the battery's voltage is what forces current to flow back into the battery for recharge. (15.5v minus 14v = 1.5 volts) this forces many amperes of current to flow toward the battery.
If either one or both has an issue, the recharge won't be satisfctory and you will be left with poor starting or no start.
As well, a faulty battery with one faulty cell cannot be recharged so the alternator keep trying to do it (alternator regulator does not know the battery is faulty) causing the battery to lose it's water in that cell first and causing more wear on the alternator.
You can begin to see the relationship of these system actions when good and bad.
Hope this covers most of it and is helpful.
Good luck.
#3
01-15-2011, 12:53 PM
Thanks Blue, I appreciate your help. As far as service goes, my parents instilled a love for this country and a believe that nothing is free. I will slowly digest all the information you passed on to me and try to follow your instructions to get my baby running smoothly. Thanks again for your time and wisdom.