New van with p0340 code
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New van with p0340 code
Hi new here and just picked up a 2002 e350 w/v10. Bought it knowing it had the p0340 code and supposedly the previous owner spent some time trying to correct it including a new sensor, ecm, and various other things. Any suggestions. Light came on during first test drive then didnt come on all day when i bought it, then came on today and hasn't went off. Truck runs pretty smooth with and without the light on. Any suggestions please post them. Oh ya checked the alternator at autozone today as well because i heard it could trip a code.
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Alright new update. Checked continuity between the cps pin coming off the pcm and the sensor itself and it has continuity. Is there a way to check power coming off the pcm itself, little nervous about unpluging the harness from the pcm and turning the key to on. Will this damage anything? Havent checked the return side of the sensor to the pcm yet because i think it changes colors in the harness.
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Im thinking its the pcm more and more. Checked all wires in the harness for a short to the sensor wires and no shorts. Continuity to both wires from sensor to the pcm plug. No voltage even while running, checked against battery ground and against the pcm ground wire. Wonder how much $$$$ this will be.
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I guess i could that but i did the test in the book about testing the sensor using a metal object and the ac volts will fluctuate, but it did nothing with my meter. Im using a fluke 902 tru-rms meter. I tried the test with a new sensor too using a metal object (wrench) and passing thru the mag field. Please explain how to conduct this test to me. I simply attached my meter to both pins on the sensor set it to AC volts and nothing! ut regardless i should have voltage to the sensor while running right?
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Mike from 5 star is helping out on the situation. He is a real stand-up guy. Barely dealt with him but already impressed. PCM in route yay!!!
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Not many responses but heres an update. Got new (used) pcm from mike at 5 star. Same thing as other pcm. Getting .3v at sensor connector. I cut the dk grn wire (signal wire) at a few inches from pcm and same reading to ground or return circuit. I am supposed to be getting roughly 12v at this sensor right? Hooked up volt meter at sensor and set to ac volts at with the truck running bounces around .14 to .21 or so volts. so it looks like the sensor is reading. What can be causing the pcm from sending 12v out of the sensor terminal?
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I seriously doubt the PCM would put 12V on that circuit. It's reading the voltage coming from the sensor, it shouldn't be supplying voltage at all.
Here's something I just found, and I was going to suggest it before I found it, but ... did you check the alternator? Do the lights flicker at all when it's idling? Connecting that volt meter on AC volts to the B+ on the alternator and ground, what do you get?
2006 Mustang GT with trouble code p0340 - Ford Mustang Forums
It seems that a bad alternator can cause this...
Here's something I just found, and I was going to suggest it before I found it, but ... did you check the alternator? Do the lights flicker at all when it's idling? Connecting that volt meter on AC volts to the B+ on the alternator and ground, what do you get?
2006 Mustang GT with trouble code p0340 - Ford Mustang Forums
It seems that a bad alternator can cause this...
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Thanks krewat, I keep reading conflicting things on what this sensor should be sending out to the sensor. I was thinking the same as you because the sensor generates a current so I was thinking the .2v I'm getting could be right. I thought about the mustang issues as well and had my alt tested at the local autozone but I've heard their test might not be good enough. Another thing that is confusing me is why it runs and idles fine even with the sensor disconnected. I thought some people had to walk home when this fails.
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Without really going into it, I'm going to say you are getting a decent signal from that CPS - it's about exactly what an ABS sensor puts out - which is basically the same thing.
The CPS on the gasser is not the only thing telling the computer anything about the engine. The CPS on the diesels WILL leave you on the side of the road.
On the gasser, we also have the crank sensor, which is just as important as the cam sensor. The cam sensor is for TDC on cylinder #1, the crank sensor is for every cylinder. Even only ONE reading from the cam sensor, and the PCM can keep track of which cylinder it needs to fire.
So, if it starts, once running, the CPS can be disconnected, and it won't stall.
Check the B+ voltage at the alternator with it running with a volt meter in AC volts and report back what you find. Not that I know exactly what it should (not) be, but it'll be a start.
The CPS on the gasser is not the only thing telling the computer anything about the engine. The CPS on the diesels WILL leave you on the side of the road.
On the gasser, we also have the crank sensor, which is just as important as the cam sensor. The cam sensor is for TDC on cylinder #1, the crank sensor is for every cylinder. Even only ONE reading from the cam sensor, and the PCM can keep track of which cylinder it needs to fire.
So, if it starts, once running, the CPS can be disconnected, and it won't stall.
Check the B+ voltage at the alternator with it running with a volt meter in AC volts and report back what you find. Not that I know exactly what it should (not) be, but it'll be a start.
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Here's the TSB for it, says it's only the 4.6 and 5.4 3-valvers, but who knows.
06-19-12***DTC P0340/P0344/P0345/P0349 - 4.6L 3V AND 5.4L 3V
Interesting information about how it would look on an oscilloscope...
06-19-12***DTC P0340/P0344/P0345/P0349 - 4.6L 3V AND 5.4L 3V
Interesting information about how it would look on an oscilloscope...
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