Been watching here for a long time. I trust you. You know what you are talking about. 96 WINDSTAR DPFE SENSOR. VAN RUNS FINE WHEN IT IS UNPLUGGED. PLUG IT IN AND IDLE GOES ALL OVER THE PLACE, LIKE A MISFIRE. CHANGED IT WITH A JUNKYARD ONE, SAME SYMPTOMS. GETTING CODE P340 CKP SENSOR, BUT WE CHANGED THAT AND THE SPINNING THING UNDERNEATH. ANY IDEAS?..
153000 miles
It would be a lot easier to read if YOU TURNED OFF THE CAP LOCK KEY!
And stick to the original thread.
http://community.cartalk.com/posts/list/2142390.page
If I interpret what you’re posting here correctly, you’re saying that you unplug the CAM position sensor and everything runs okay. Plug it in and stuff goes screwy. You tried one from a junkyard and it too produced the screwy results.
You also changed the rotor while you were there.
The cam sensor triggers the fuel pulse in the whole mix. Since you have the distributor cap off, I would check to see the condition of the timing chain. Simply turn the crank by the pulley bolt and watch for the distributor rotor to start turning. Turn the crank the other direction and see how many degrees of rotation it takes for the rotor to move again. It should be no more than something like 12 degrees at the crank. If it’s more than that, you need a timing chain.
It wouldn’t run without the cam sensor. I’m sure the OP is pulling the DPFE (EGR flow) sensor. I guess that indicates that there’s some short or other odd issue between the cam and the DPFE sensors.
The 96 doesn’t have a distributor or a rotor. Unlike some, I respect the OP’s desire to only get aid from someone who knows about their particular car.
Excellent: Then how would you interpret this statement?
, BUT WE CHANGED THAT AND THE SPINNING THING UNDERNEATH
What “spinning thing” is he referring to? I mean, since you’re someone who knows about who deserves the respect that some show no regard for?.
Most of the Vulcans that I’ve seen indeed had a dizzy …but that surely could have gone the way of the dodo.
This should be the spinning thing that the cam position sensor rides on top of. the remaining leftovers from a distributor.
btw- did you bother to augment the code he said he got? P0340 is the cam position sensor.
The DPFE sensor simply measures the pressure drop in an orafice (restriction) designed into the EGR exhaust path when the valve opens. The purpose of the orafice is to create a pressure drop, the purpose of the DPFE sensor is to sense this and tell the ECU that the EGR valve is working. The whole DPFE system is designed to monitor EGR valve performance.
Since the problem is in the idle and disconnecting the DPFE sensor smooths the idle, let me suggest that perhaps the EGR valve is remaining open, feeding exhaust into the pathway when it should not be. The DPFE sensor would be sensing the differential pressure inappropriately and the ECU would respond inappropriately, adding fuel and driving the idle up.
Perhaps the valve and the orafice are both clogged up with carbon residue.
NOTE: trying cleaning the valve and orafice is FREE! If I’m crazy, you’ve lost nothing.
VAN RUNS FINE WHEN IT IS UNPLUGGED…Hey! here is an idea! Just leave the thing unplugged!! Cost ZERO. Engines ran fine for 70 years without EGR valves. So will yours…
So if the CEL stays lit eternally, how will the OP know if something serious develops that the CEL would have otherwise notified him of?
I recommend against simply ignoring the CEL warning. I think it’s a better idea to get the car fixed. The DPFE symptom, idling poorly when connected and fine when disconnected, is a great clue. And since the DPFE’s function is to monitor the EGR circuit, I’d recommend checking the EGR circuit as a next move. Since the DPFE sensor has already been changed it seems logical that the thing it’s monitoring is a good place to look next.
That’s my feeling. I know the OP requested specifically OK4450, and I too have only respect for his knowledge, but until he posts I’ll take the liberty of suggesting my own thoughts on the problem. Can’t hurt.
My interpretation is that the cam sensor and the DPFE were both changed. The 96 has distributor-less ignition.
Yes, I am aware that the code is for a CAM sensor. The OP says that when he unplugs the DPFE, the cam sensor starts working correctly. (Of course, he then gets an EGR code.)
The OP wants to know what the DPFE and the cam sensor have in common besides the PCM. I don’t have the wiring diagrams to the 96 Windstar, so I don’t know. Clearly, an interaction has been determined.
What you are missing here is that it throws a cam sensor code when the DPFE is plugged in. I don’t think it’s an EGR problem, nor did I get the impression that it was only an idling issue. It seems like plugging in the DPFE some how messes up the cam sensor signal. Of course, I’m just guessing here too.
I caught that but it made no sense to me. The only thing that makes sense for the DPFE doing that is the EGR circuit, recognizing that the sensor itself has been changed, so I went with logic. But I admit that it’s a guess.
It’s a Windstar van with 153K miles on it. NOTHING a CEL lights up for is “Serious” at this point. It drives okay or it doesn’t…
Oil lamp is out, temperature gauge is OK, it drives fine…So drive it and keep your money in your wallet…
This OP asked for input from one person, and it seems that person is the only regular who hasn’t responded. I don’t think he trusts anyone else right now.
Well, I think the praise is a bit overblown. I’m somewhat knowledgeable on certain cars and areas and not so much in others. Even though I’ve owned and do own a lot of Fords and even used to do a bit of sidework for a now deceased Ford dealer I don’t even consider myself an expert on those; more of a Parts Replacer of Unparalleled Magnitude. 
That being said, I often consider some salvage yard parts to be real iffy at best and the DPFE is one of them. Right up there with used fuel pumps or water pumps.
Since the idle is going stupid when it’s plugged in maybe the problem is not the DPFE but is the vacuum solenoid instead, which could be trying to hold the EGR open a little.
Try blowing through it. If you can blow air through it’s likely faulty.
The next test would be connecting a ground source and power source to the vacuum solenoid. With power applied you should be able to blow through it. If not, the solenoid is faulty.
I’m curious about this spinning thing, whatever that is. Are you referring by chance to the EGR pintle; which is a needle and does not spin?
OK4450, you’re entirely too modest.
Guys, I think we lost another OP.
No surprise. It seems that too many people don’t bother to post back with the report on whether or not our suggestions worked out for them. This is frustrating and keeps us from learning how good our advice is.
The OP mentioned replacing the crankshaft position sensor (probably also with a junkyard part) at the same time as the spinning thing. My guess is that the spinning thing is the reluctor ring mounted to the crankshaft that the crank sensor reads off of. This part should not need to be replaced unless it is damaged. My other question is why one would buy a DPFE sensor from a junkyard. They are not that expensive new and are one of the most commonly failed parts on a Ford engine. The junkyard one is likely to be bad also, if that were actually the problem.
Did the timing belt jump? Was it ever changed? After a while these do strech. after a long time they can jump.
The 1996 Windstar had either the 3.0L or 3.8L V6. Both are OHV engines with a chain driven camshaft. No timing belt in either engine option. It is possible for chains to slip or jump, but it is rare with either chains or belts. It sounds like this vehicle either has an electrical problem, bad sensors (a couple were evidently replaced with junkyard parts), or an EGR flow problem. I’m not trying to shoot down your suggestion, just putting my 2 cents in.
The DPFE goes bad often.I wouldn’t replace it with a used part.I agree with mountainbike, if the DPFE is new, take off the EGR valve and clean it with WD 40 to soften the carbon build-up,clean the orifice. Also verify the exhaust signal the DPFE is getting. A smoke machine is helpful , it will verify vacuum leaks, including the EGR valve diaphragm.