Crank position sensor. Oh what a fun time

Ok. It took a couple hours to get the bolt out and then a while longer to find it when I dropped it. After trying to get the connector off with multiple attempts from above. From the side. From below I finally figured out why it was stuck. There is a a little plastic piece on top that directs the wires 90 degrees away from the sensor. That plastic piece was preventing me from depressing the little plastic lever so it could slide passed the ramp lock. šŸ˜”

Now of course I've discovered that the plastic sensor has done the impossible and alloyed itself with the surrounding metal and won't even think about moving. No way to pry in there and twisting is proving to be a challenge. Fitting any tools up there is beyond the basic laws of physics.
 
From what I can see right now. If I cannot get the sensor free there is no room to get on it. The next step is pulling the intake manifold and fuel rail just to have any sort of access. Looking for any tricks others have because....I'm going after it with a hammer and prybar now.
 
I've done the best thing I can right now. Put away my tools, closed the hood, and walked away. I'll calm down a bit, get some pb blaster and start soaking the area. If a couple of days of penetrating oil don't free it up I'll consider the next more complicated approach.
 

Patrick of M

2005 T1N 2500 (NA spec)
I'm going to say the same thing I written elsewhere . Are you 100 % sure you need to replace the sensor? I know sensors fail, but a position sensor is just a little coil being aroused magnetically, you can test in situ fairly easily.. Does it have continuity/does it generate a signal when whatever is supposed to move past it, moves past? Most of the position sensors I have had problems with were wiring harness/plug problems.
 
I know the ecu has power. I know the fuel pump is working and the engine has fuel to the injectors. I know all the relays are working and all the fuses are good. I know all my grounds are good as is my battery and battery cables. I know I put a brand new EGR valve in the morning one day. Drove the van that day about 25 miles with one shut off in between and the second time it shut off it never started again. I know the injectors are not firing. I know I put a new camshaft sensor in because what the heck it was cheap and easy. It's either a bad crank sensor or a bad wiring harness. My harness is rout d nicely with no kind of kinks or signs of damage. While it is possible it's in the wiring it's usually easier to put in a new sensor instead of dissecting my whole harness. Plus my experience with other cps is that they work one day and then not the next. I have no scanner to plug in but the fact my injectors are not firing but my ecu has power leads me to a failed sensor. At this point my question is about getting the sensor out. If a new sensor doesn't start the van then I will go after wiring.
 

lindenengineering

Well-known member
The proper answer is to remove the transmission and beat out the old sensor with a bent punch.

Then!
With a rotary brush and drill clean out the hole, apply some dialectric grease to the sensor body and install it.
Easy and quite do-able (or should I write achievable) with some basic tools/kit and some enthusiasm.
Should take you 5 hours of fun!
Dennis
 

lindenengineering

Well-known member
That will take you longer!
R,n,r (re-fit)with gasket etc etc the manifold is at least 6 hours and you run the real risk of having a broken part trapped in the hole !!
Then you are going to be forced to remove the transmission anyway!
Think and repair smart remember, and if you are working on flat rate like most American mechanics you will be going hungry this coming week even though you bust yur ball trying to fix it .
Std job time is 5,5 hours plus 0,5 hours for road test & diagnostics.
Customer will refuse to pay for diddling about of course so you will pay for wasted time & lost productivity !
Most of my guys can do this in 3 hours earning a profit sharing bonus each month and we don't do flat rate! (Euro style shop repairs rule!)
Dennis
 
Key off the resistance measure across the connector itself is 17.5k ohms. With the key on and referencing each terminal to ground I get 2.5 volts at each terminal.
 

lindenengineering

Well-known member
awsome. I'll buy you a six pack of your favorite beer. The van is in Vermont. When can I expect you?
Yes OK!
If you will cover my travelling & accommodation expenses and repair time at $150/hr call out rate I will be there in two days.
Please call me with a credit card number at hand and i will arrange with you an arrival date.
Let me know!
Dennis
 

surlyoldbill

Active member
Still going back to cause and effect; the only thing you did to the van between it working and starting all the time and then it NOT is replace the EGR?

Maybe EGR wiring?
 
yes. That's about what I thought the response would be. I'll stick with pulling the intake manifold but I appreciate your attempt at advice. Actually I'll liberally soak the area with penetrating oil for a few days and if that fails I'll work from above. Y
 
Still going back to cause and effect; the only thing you did to the van between it working and starting all the time and then it NOT is replace the EGR?

Maybe EGR wiring?
I actually started the van, drove 8 miles and picked up 5 sheets of 1/2" thick Zip panels at the lumber yard. Then I restarted the van and drove 3 miles up a mountain pass and stopped at a store to get cash at an ATM. Then I restarted the van and drove another mile or two over the top of the pass and 8 more miles into the town below where I went to the dump. Went across the scales and backed into the drop off area. I shut down and empty out my debris. This time the van did not restart. That's when I checked all the fuses, relays, shifter, instrument lights and Gage's, verified transfer pump operation and fuel flow. Then also verified the injectors were not firing.

I'd expect that the EGR wiring would cause a LHM condition and I didn't have any lhm. I do have a CEL but no way to check it at the moment and had thought it was left over from my earlier issues with the EGR. Today I checked both wires on the CPS plug and they seem to be connected with signal. I cannot check the sensor operation or lack of operation.
 

Patrick of M

2005 T1N 2500 (NA spec)
Key off the resistance measure across the connector itself is 17.5k ohms. With the key on and referencing each terminal to ground I get 2.5 volts at each terminal.
So without knowing the specs, it sounds like the sensor is intact. I would guess that with the engine turning over the sensor then produces a pulse of some sort. A bit complicated to read, sometimes it's just a frequency, but I really don't know.
I really don't see the point of grinding yourself into the ground pulling bits that aren't necessarily the culprit. I've done this myself, chasing down problems. I mean yeah, maybe it is the cps, in which case great (and it does sound like you have trouble shot pretty close) but wouldn't a good Snap-on/ or similar scan from a local mechanic remove clear things up faster? Some mechanics are quite reasonable in what they charge, doesn't have to be a crazy dealership cost.
Just thinking out loud....good luck!
 

doug022984

Sporadic Member Since 2015
I cannot check the sensor operation or lack of operation.
Does it crank and not start? If it cranks and you see the tach needle rise a little while cranking, your CPS is working. If the tach needle doesn't move at all, then it's probably the crank sensor.

If you do find out that it's indeed a bad crank sensor, then I agree with Dennis that taking the manifold off to get at it is a lot of extra work. If you haven't already, I suggest removing the starter first. Much simpler to do and it will give you more space to get hands and tools up to extract the sensor. Attached is a pic of the side of the engine to help show all the crap that would have to be removed to get the manifold off and also the big gaping hole you have with the starter removed right under the crank sensor.
 

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