Escapable
07-02-2013, 08:43 PM
Here I was driving along and began thinking ... This is really running good .. at last, finally rid of that annoying misfire rough running thingy.
Dreams are made of this stuff ... then into the car next day ... chug chug chug twang .. nothing but that chrysler wound up spring starter sound ....mmmmmmmmmm
ODB reader (ELM327 on PC) showed P0320 - CKP or Crank Position Sensor - no input received by PCM.
No Warning, interesting.
Removal was easy on this 98/99 XJ Grand Limited, long bar, 7/16 socket and universal joint on the end (20 mins changeover, but make sure the exhaust is cooled as YOU WILL get burnt) .. easy .. so how do you test this ..... not so easy unless you have some equipment .. suggest an analogue meter (digital is prob OK, but you need to interpret the results and digital meters can misread in auto use) and look at the pulse output whilst cranking the engine over; analogue will show needle deflection or shudder (it is up from near zero to 5v); no output, new sensor or possible wiring but they do have a plastic shield around them - my sensor had the output shorted to the signal ground, so it was dead.
To test this sensor out of the car you need to put + and -5volts (or near) onto the correct terminals; move a magnet across the tip of the sensor and it should pulse (output and signal ground terminals - note NOT car ground) if it's OK, however if the scantool shows P0320 change the sensor and start the car!
Dealer price for p/n 04897321AA was $235, 4x4point $109, local auto $105.
Installing is also fairly easy once you get the bolt in the hole (this was not too bad from the top, although frustrated by the wiring heat shield), simply use the long shaft and universal joint again and connect the lead making sure its routed correctly across the top of the bellhousing.
Now waiting on a spare one for under the back seat - cheap insurance.
Scantool ... the ELM327 (v1.4) in USB (recommended) is around $20 and scantool software is out there for download so there is no reason not to have one.
NOTE: After changing this sensor the first time, I had another bad sensor (obd P1391; Intermittant failure of Crank or Cam sensor) that I received from a QLD parts retailer (it looked used, had rust and marks where it had been prev used ...one wonders, but another happily LOST customer) - it is cheaper to get the Tridon (www.tridon.com.au (http://www.tridon.com.au)) one from the local auto spares and also remove the sticky bit on the end before instal - and before the flamers say it was wiring .. NOPE.. it was all checked and another sensor even removed that random mosfire that had me thinking about distributor wear!
Point of interest: Only in reality would an oscilloscope find this random event .. you aint getting my nice clean lab equipment under a bonnet!
End of muse: believe the magic of the scantool - for it sometimes is even believable or at least more so than the JEEP specialist (and believe a little of what google has to offer as well) ... just gimme back my old points n carbie!
In reality all of the spares I have used have been available from local spares suppliers, cheaper thean the so called specialist suppliers ... try them and compare, you will be amased. - in this case the dealer was cheaper than some of the quotes for after market sensors.
Dreams are made of this stuff ... then into the car next day ... chug chug chug twang .. nothing but that chrysler wound up spring starter sound ....mmmmmmmmmm
ODB reader (ELM327 on PC) showed P0320 - CKP or Crank Position Sensor - no input received by PCM.
No Warning, interesting.
Removal was easy on this 98/99 XJ Grand Limited, long bar, 7/16 socket and universal joint on the end (20 mins changeover, but make sure the exhaust is cooled as YOU WILL get burnt) .. easy .. so how do you test this ..... not so easy unless you have some equipment .. suggest an analogue meter (digital is prob OK, but you need to interpret the results and digital meters can misread in auto use) and look at the pulse output whilst cranking the engine over; analogue will show needle deflection or shudder (it is up from near zero to 5v); no output, new sensor or possible wiring but they do have a plastic shield around them - my sensor had the output shorted to the signal ground, so it was dead.
To test this sensor out of the car you need to put + and -5volts (or near) onto the correct terminals; move a magnet across the tip of the sensor and it should pulse (output and signal ground terminals - note NOT car ground) if it's OK, however if the scantool shows P0320 change the sensor and start the car!
Dealer price for p/n 04897321AA was $235, 4x4point $109, local auto $105.
Installing is also fairly easy once you get the bolt in the hole (this was not too bad from the top, although frustrated by the wiring heat shield), simply use the long shaft and universal joint again and connect the lead making sure its routed correctly across the top of the bellhousing.
Now waiting on a spare one for under the back seat - cheap insurance.
Scantool ... the ELM327 (v1.4) in USB (recommended) is around $20 and scantool software is out there for download so there is no reason not to have one.
NOTE: After changing this sensor the first time, I had another bad sensor (obd P1391; Intermittant failure of Crank or Cam sensor) that I received from a QLD parts retailer (it looked used, had rust and marks where it had been prev used ...one wonders, but another happily LOST customer) - it is cheaper to get the Tridon (www.tridon.com.au (http://www.tridon.com.au)) one from the local auto spares and also remove the sticky bit on the end before instal - and before the flamers say it was wiring .. NOPE.. it was all checked and another sensor even removed that random mosfire that had me thinking about distributor wear!
Point of interest: Only in reality would an oscilloscope find this random event .. you aint getting my nice clean lab equipment under a bonnet!
End of muse: believe the magic of the scantool - for it sometimes is even believable or at least more so than the JEEP specialist (and believe a little of what google has to offer as well) ... just gimme back my old points n carbie!
In reality all of the spares I have used have been available from local spares suppliers, cheaper thean the so called specialist suppliers ... try them and compare, you will be amased. - in this case the dealer was cheaper than some of the quotes for after market sensors.