have a weird one. 94 XJ with the straight 6. haven't had any real issues since i've owned it. come home from the store, go to fire it the next day and it won't start. i verified fuel pressure at the rail. tested the coil and crank sensor. i've since read the crank sensor test is unreliable {testing for 0.00 with an ohm meter on b&c}. am curious what some of the seaonsed vets think of this. the not just dying in traffic part is what's kind of different. the jeep drove me home just fine, just won't start back up. curious if this specific condition has a common problem

only codes are 12 and 55 so that's no help

 

Have you tried starting in neutral?

 

just did, nada, reverse lights work, checked that while i was at it. spins over quick but not even the slightest hint of spark

 

check the ground wires to the block coming from the inside? fuses?

 

need to trace ground wires, did check all the fuses

edit. on the crank sensor test i received 0.00 which is a short the two test terminals. is that correct? i notice the test mentioned "open" when i think of an open circuit i think of a light switch. if the sensor is in open should it be testing as a short?

 

Terminals B and C should not read zero ohms. Should read very high or infinite resistance (open circuit).

Touch the test leads together...you should get a reading of 0.00 ohms, a dead short. If you are getting the same reading testing the CPS...it's shorted. Anything less than 1-2 Megohms resistance is suspect for a '91 or newer.

 

will double check this tomorrow when it's light out.

if this winds up being the problem. i've ruled out using the el-cheapo parts, just am curious if there is much of a difference between the good $68 standard PC41 and the OE dealer unit. i noticed standard has the cheaper T series but i'm not trying to save a couple bucks on a part that's pretty important....and doesn't look fun to change. doesn't look hard really, just one of those "oh boy" it's way up there type things. good thing i have a lot of wobble extensions and an 80 tooth snap on flex ratchet

<--- this one

 

Pro tip:
Don't drop the bolts into the bellhousing! When installing the bolts, I loosely duct tape the bolts to the socket so they don't fall out when trying to get them started; just enough so they won't fall out of the socket, but not enough to where you can't pull the socket off the (installed) torqued bolts with the extension(s).

 

this is easier than my idea. i was considering gluing a magnet into the back of the socket

read a few of those "uh oh i dropped the bolt inside" threads. didn't sound fun

what's a guy do if that happens anyway? drill a 1/2" hole in the bellhousing at dead bottom?

 

There should be an inspection plate, for an auto anyway.

And a dab of greese inside the socket does the same basic thing as tape.

 

just tested the sensor, reason i was getting zeros on 20k was the amount of resistance the sensor actually has. my cfs has 10ohms. yes ten. double checked it against a 10ohm resistor and they test the same.

also, where is the inspection plate? i could probably find it digging around, all i remember seeing under there was the sensor and a little plate it appeared to be shimmed with

 

On the bottom f the bell housing.

 

I had to pull the starter and go fishing with one of them pen magnets lol!

 

My general rule of thumb is: if the part can damage the vehicle or leave it stranded, or is a nightmare to change....use the OEM part. Some of the aftermarket stuff is just fine, some not. Problem is you have to sort them out the hard way, lol. The OEM stuff seems to be more consistent.

 

You'll find hundreds of threads related to failing/failed crankshaft position sensors. The general consensus is that these parts should only be replaced with OEM units from the stealership. Aftermarket units are known to have a high failure rate. I only wish they'd have put the damn things lower on the bellhousing. Like next to the starter would have been great!

I bought one from NAPA at $93. Went to all the trouble to put it in only to find that it didn't work, and actually made my XJ run WORSE than it had been. So off to the Jeep dealer I go. $117. Half a day, two scraped knuckles, and lots of quarters in the cuss jar later it was running smooth as silk. In hindsight, I'd have been much happier to pay the dealer $175 if it would have kept me from changing it twice.