Camshaft testing with a multimeter

Tiny
KHURLEY1969
  • MEMBER
  • 2002 FORD RANGER
  • 3.0L
  • V6
  • 2WD
  • AUTOMATIC
  • 90,000 MILES
Truck will crank but won't start. All fuse and wires have been checked, changed as needed. When I use my multimeter in DCV I get a steady 1.5 reading but when I crank the truck in AC it gives me a steady 2.5 reading. I have removed the crankshaft from the truck and tested it appears to be good.
I'm not sure what else to do next or if I've done the test wrong. Can you please send me your ideas?
Thanks
Sunday, March 13th, 2022 AT 5:07 PM

7 Replies

Tiny
JACOBANDNICKOLAS
  • MECHANIC
  • 109,885 POSTS
Hi,

Does the vehicle have spark to the spark plugs? Also, have you checked for diagnostic trouble codes? The power at the sensor from the PCM should be between 1.0v and 2.0v. You are right where it should be. If you are checking the sensor signal to the PCM, it should produce around 300mv (on average).

I noticed you are mentioning specifically the crankshaft position sensor, but there could be other things causing it. Again, I'm not sure what pointed you in that direction, so you may have a specific reason.

If you haven't checked for spark, do that. The easiest thing to do is see if it starts for a couple of seconds using starting fluid. If it does and then stalls, we know if its fuel related. If there is no change, then it's likely ignition related.

Let me know as much as you can. Also, remember there is an external trigger wheel that the sensor uses. Make sure it isn't damaged or loose.

Let me know.

Joe
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Sunday, March 13th, 2022 AT 7:28 PM
Tiny
KHURLEY1969
  • MEMBER
  • 4 POSTS
Joe,
Thank you for your prompt reply.
You requested as much information as possible so here we go:
I've rebuilt the inside of this engine approximately 5 years ago it's got between 80 and 90,000 miles on the engine. I do not think there's anything wrong with the timing chain. However, within the past year I have had to replace replaced the outer engine accessories ignition coil, wires, spark plugs, fuel injector, airflow mass sensor, idle control valve, throttle position sensor, ignition switch, purge valve, engine coolant temperature sensor, product pressure regulator, camshaft position synchronizer sensor, crankshaft positioning sensor by the crankshaft next to the wheel with the 32 teeth, the fuel pump, anti-theft light bulb was out replaced it it's back on, wire was burnt off of the knock sensor replaced it
I am getting power to my coil, but I am getting no power to my wire or spark to my spark plugs. I have tried testing and starting the truck with starter fluid it will not. When cranking you can clearly smell fuel, so I know the injectors are working. Testing my coil with my multimeter set to 20K my results are 1and 6 gave me 12.40, 2 and 5 gave me 12.46, 3and 4 gave me 12.42.
Checking for resistance using my ohm setting all of my pins registered a 1.5, checking for continuity all of my spark plug wires registered 0.00 which I'm led to believe means there's no breaks in the wire.
Not sure how to check my PCM for power. Attempted to scan with my Creader VIi+ but because the battery was disconnected and then reconnected, I'm not showing any codes currently.
I have power to all items listed below:
Alternator, air flow Mass sensor, throttle positioning sensor, fuel injectors, idle control valve, power to engine coolant temperature sensor, fuel pump (I can hear it run and the pressure is between 59 and 60), knock sensor, purge valve, power to the starter relay and it is cranking over. Power to the crankshaft positioning sensor reading on my multimeter in the DCv is 1.5 the truck is off. With my multimeter set on AC while cranking my multimeter registers 2.5.
I am getting compression off of 1 2 3 4 5 6 cylinders anywhere between 150 to 190.
PCM female adapter (wiring harness) disconnected from pins tested on multimeter setting dcv20 results:
Wires in order 1-104
1)12.28, 2)12.32, 3)12.32, 4)12.23, 5)12.33, 6) 0.09, 7) 0.00, 8)0.01, 9)0.00, 10)0.04, 11)0.08, 12)0.08, 13)0.08, 14)0.02, 15)12.32, 16)12.32, 17)12.32, 18)no wire, 19)12.32, 20)no wire, 21)12.32 22)12.32 23)12.32 24)no wire, 25)0.01, 26)no wire, 27)12.32, 28)12.32, 29)12.32, 30)0.00, 31)0.00, 32)no wires, 33)0.08, 34)0.00, 35)no wires, 36)0.08, 37)no wires, 38)0.08, 39)no wires, 40)no wires, 41)12.30, 42)0.02, 43)12.30, 44)no wires, 45)12.31, 46)no wires, 47)12.30, 48)12.30, 49)12.30, 50)0.01, 51)0.01, 52)12.26, 53)12.28, 54)12.28, 55)0.00, 56)10.70, 57)no wires, 58)0.00, 59)no wires, 60)no wires, 61)0.00, 62)0.02, 63)0.08, 64)0.07, 65)0.07, 66)0.01, 67)0.0, 68)no wires, 69)no wires, 70)0.05, 71)no wires, 72)no wires, 73)no wires, 74)0.04, 75)0.08, 76)0.08, 77)0.01, 78)12.21, 79)12.26, 80)12.18, 81)0.08, 82)no wires, 83)no wires, 84)0.08, 85)no wires, 86)no wires, 87)no wires, 88)no wires, 89)no wires, 90)1.63, 91)0.00, 92)0.00, 93)0.00, 94)0.00, 95)0.00, 96)11.62, 97)no wires, 98)no wires, 99)0.00, 100)0.00, 102)no wires, 102) 0.01 103)0.01, 104)12.20
I do not know what these wires correspond with. Not real handy when it involves the wiring of a vehicle.
I would greatly appreciate any and all help you could send my way. Hopefully the information above gives you some idea why my truck is cranking but not starting.
Terry
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Monday, March 14th, 2022 AT 4:42 PM
Tiny
JACOBANDNICKOLAS
  • MECHANIC
  • 109,885 POSTS
Hi,

Wow, you've done a lot of work on this. Regardless, the coil on this vehicle should have power at all times when the key is on. You've confirmed that already. Power should be on the red wire with a light green tracer at the coil.

Here is how it works. Each coil within the pack fires two spark plugs at the same time. If you look at the pic below, the three wires (other than the power) should receive a ground signal when the PCM determines it should provide spark.

In this case, you need to check if there is a ground signal being provided. So, check for a signal at any of the three wires when the engine is cranking and let me know what you find.

Also, please confirm for me that the red/light green wire is the one with power.

If you get no ground signal, then it's time to start checking the CKP circuit which is a bit more involved. If you look at pics 2 and 3, I provided the wiring from the CKP to the PCM. The remaining pics are the steps for testing the CKP circuit.

Let me know if this helps and what you find. If you have questions, let me know. Note: If there are no issues between the CKP and PCM and the wiring between the coil and PCM doesn't provide a signal ground, then there is a change the PCM has failed. However, make sure the trigger wheel is not loose or damaged.

Let me know what you find.

Take care,

Joe

See pics below.
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Monday, March 14th, 2022 AT 7:00 PM
Tiny
KHURLEY1969
  • MEMBER
  • 4 POSTS
Joe,

I would like for you to know how much I greatly appreciate all the help and assistance you have given me and hope that you will continue to help me in the future.
Okay so following your suggestions in testing my coil the red and light green were my power, but what I also found was all three tan and colored wires also had power. Testing with a test light none of them fluctuated, none of them acted as if they had a ground or a switch signal. I began testing my ckp circuit and rechecking the wiring, and my PMC I was still getting the 1.5 and the 2.5 on my multimeter so I began tracing a dark blue and gray wires from my PMC back toward the camshaft I followed them down till they met up with the bundle of fuel and alternator wires at this time I noticed that the dark blue and gray wires appear to have some type of aluminum coating as well as a bare wire. Continue to trace and found that the bear wire was not connected it was about 6 in short. (I could not find this combination of wires or any mention of it in any book, diagram or video that I have found as of yet) I have a old 2000 3.8 V6 that I've repaired sitting in my garage. So, I investigated it and found the same blue, gray, and bare wire combination. I scavenged it and put it on my ranger. Connected everything back up and went about retesting and then decided what the heck let's just see if she'll crank not only did, she crank but she turned over and ran. After letting her run for a little bit, I put my code reader on her and the code that is now coming up is a PO 340 camshaft positioning sensor a circuit bank 1 or single sensor. Could you help me out with that please?
Thanks in advance.
Terry
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Tuesday, March 15th, 2022 AT 7:47 PM
Tiny
JACOBANDNICKOLAS
  • MECHANIC
  • 109,885 POSTS
Hi,

As far as the sensor is concerned, I attached the relevant diagnostics below for the P0340. Take a look through them and let me know if they help.

Take care,

Joe

See pics.
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Wednesday, March 16th, 2022 AT 1:22 PM
Tiny
KHURLEY1969
  • MEMBER
  • 4 POSTS
Joe,
The information was helpful yes. Another frayed wire. Thank you so much for your time and energy.
Terry
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Thursday, March 17th, 2022 AT 3:22 AM
Tiny
JACOBANDNICKOLAS
  • MECHANIC
  • 109,885 POSTS
Hi,

You are very welcome, and thanks for the update. I'm glad to hear you found the issue.

Please feel free to come back anytime in the future if you have questions. You are always welcome here.

Take care of yourself,

Joe
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Thursday, March 17th, 2022 AT 2:59 PM

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