can the crankshaft sensor go out without throwing a code?
gonna check voltage at the coil input. i'm guessing that I need to check voltage to a different ground. the pcm controls the coil ground, right?

 

didn't get out the multimeter, but I checked both terminals on the ignition coil plug with a trouble light to an independent ground and didn't get anything. is there a relay in the pdu that's compatible with the starter relay?

 

Any of them. Remember, you only get power for about three seconds after you turn the key on, then the PCM turns off the ASD relay, till it sees the motor turning.

 

If the crank position sensor goes bad, you will get no power to the coil, and no start.
If the crank position sensor is original with a lot of miles on it, it would be a good idea to replace it.
They can go bad with out throwing a code.

 

ok. thanks. I ruled out the relay using the tests in the service manual. I must say i'm a little disappointed. is there any reasonable way to test the crankshaft sensor?

 

Not without an expensive scan tool.
Only buy a OEM crank sensor.
I had damaged mine when replacing the transmission in my 96.
I bought a Napa crank sensor to put in there.
Shortly after installing when i start it the first time for the day it would run about 8 minutes and shut down.
Then it would be fine the rest of the day, until it cooled down for several hours.
Then it would do it all over again.
This went on for 6 months never throwing any codes.
Until one day it died twice within a quarter mile. then the CEL came on and it had code for crank sensor.
Put OEM crank sensor in there and haven't had any issue since then.(2008)

Dave

 

looks like I gotta run to the parts store. thank you all for the help.

 

Dealership. Not parts store. Unless they have OEM parts there. The Duralast, standard motor products, etc brands are simply not as good as the OEM feller, and our trucks are REALLY sensitive to that for the critical sensors.

 

quick question-
on the asd relay, should I have continuity between the normally open contact and ground? i'm thinking not and my coil voltage is shunting to ground causing no spark at the coil. help please!

 

i'm having some ignition problems. they came on suddenly after a few days of rain. so far I've replaced the crankshaft position sensor, camshaft position sensor, coil wire, and coil. still getting no spark. my question is this: on the asd relay socket, should I have continuity between the normally open pin and ground? I'm thinking not, but before I start tearing apart wiring bundles, i'd like a second opinion.