Will these sensors start failing intermittently?
Had a no start issue yesterday and notice that while the engine was cranking the tachometer wasn't moving.
Let it sit so the batteries could rest and then it started on about the 5th try.

 

 

If not, now is the perfect time to get one - swap it out, and if that isn't the issue, you have a critical spare.

Any stored codes?

 

No codes right now since I had the batteries disconnected all day while I went through the harness again.
Ohmed every circuit from the 42 pin plug to the connectors and found no issues. I even wiggled the wires while connected to the ohm meter to see if I could make something happen.

The new starter arrived and is sitting in the box. I noticed it was made in China so I am thinking of just sending it back.

I will check in to getting a crank position censor. Can someone tell me what the cam position sensor does? Do the two sensors work in harmony?

 

AFAIK there is no crank sensor, only a cam sensor, and without a signal there will be no injection.

 

My 02 model doesn't show rpms while cranking. Not sure what year models of 7.3 that troubleshooting tip pertains to, I see yours is a 00. Somebody else may chime in with that information.

 

Thanks for the replies.

I had gone online to find out possible solutions to my no start on Wednesday. One of them said if the tach isn't showing rpms while cranking that the crank position sensor was bad so I assumed there must be one. Then while going through every circuit on the harness and following the schematics I noticed that there is cam position sensor, hence my question.

 

Not all of our trucks show RPM's while cranking but I can't remember which do and which don't.

 

Mine started after reinstalling the thoroughly tested wiring harness. I will check to see if the tach moves next time I start it.

 

Ugh. I hate intermittents.

 

I believe that the '02 MY was the change over to a few things and tach does not register while cranking.

 

Yes, it can. One day your truck is great and another day it could stall on you a few times. Sometimes you can restart it right away and sometimes you have to wait a bit.

You won't get a generic code with a CPS issue (at least I never did). One of the times my truck died I coasted to the side of the road, left the ingnition on and tried to read the code with my generic ACTRON reader...no dice (I don't know if you would find anything with AE or FORScan).

 

My '02 Ex doesn't show RPM (tach bounce) while cranking.

 

This is a video of my 2000 F-250 starting. Best I can tell my tachometer does jump up a bit (250-300 RPM) when starting, although it is quick.

 

This thread has evolved into a Cam Position Sensor (CPS) thread regarding advice and tech while the thread still shows Crank as the topic. Just posting this as a public advisory so readers realize that point.

Stewart