2 questions:

1) What the appropriate way to check for spark with coil-on-plug setup? Just put spark tester at the end of the coil (metal part)?

2) is it safe to start + run car with camshaft sensor unplugged (98XJR)

gracias

 

1 question to answer both
WHY?

 

i have the same question as brutal..?. [sm=badidea.gif]

 

skanoski, the motor will run with the camshaft sensor unplugged. Can't garantee how well it will run. The motor will still know the relative position of the engine based on the crankshaft position sensor (atleast on a 5.4L Ford, there is a 36 -1 toothed gear on the crankshaft).

You can test the camshaft position sensor by simply connecting a multimeter across the two pins on the sensor and then passing a large screw driver by the tip of the sensor. You should see the multimeter jump slightly as the screwdriver goes by.

As for measuring a COP coil, you can do resistance measurements, but from my experience, they are very unreliable. If you are questioning whether a COP is good or not based on a code being received, swap the COP to an easy to access plug and see if the code moves to that cylinder. If it does, then the COP is bad. If it stays on that cylinder, then you are looking at either a bad plug or a wiring issue feeding the COP.

Having a Ford truck with the COP setup, I have noticed that the COP will show signs that it is failing. This is normally indicated by the resin top cracking. The motor will show signs of rough running especially when it is wet outside/run though a puddle. This is water getting on top of the COP and then getting into the COP. Also, take a good look at the boot. They are subject to heat deterioration and will effectively dry rot inside the engine. Don't know about the Jag, but on my Ford you can get replacement boots separate from the COP. Cheaper option than getting a whole COP assembly.

If you have more questions, just ask.

 

the "why" is related to a cold-start problem I'm having (described in more detail in XJ8-R forum) - I wanted to check for spark - and also thinking that if the cam sensor is bad, that the car would potentially start with it unplugged. Probably not, but it doesn't sound like it will hurt to try.