No SPARK, need some help please...

Hi there,

Got a 91 XJ with the tranny(ax5) out of it at the moment. I have been trying to get it to start, but get no spark whatsoever.

Have tested the coil and checked out the PCM and they seem to be working fine. I also have the crankshaft sensor up near the flywheel with a magnet holding it on(since no tranny is in atm). have the distance sensore plugged into the tranny sitting below the XJ. I'm at a loss as to why there's no spark.

My question is this:

What am I overlooking here? I get no spark whatever I do. Could there be a safety switch or something? I need to start it without a tranny, if it's running well then I'll go pickup a tranny for it.

Anyone have any troubleshooting ideas?

Anyone familiar with any of this?

Thanks for your time, will check back on the board in a bit.

Flip

What about the neutral safety switch?? Its connected to the transmission and only allows it to start in neutral or park........just an idea. Also did you check the ballast resistor?

Hi there,

It's an AX5 manual tranny, wasn't sure if it'd have a neutral safety switch on it, does it? There was a couple of wires that ran to a inlet by the shiter input, I hooked those up as well hoping if it did have a safety, that would fool it.

Not familiar at all with the ballast resistor, I'll go look into that and check back in a bit.

Thanks for the reply, really appreciated. Any other thoughts you guys can come up with while I'm out there would be greatly appreciated.

Flip

If you have the crankshaft sensor held in place with a magnet it will not start. The sensor has to be mounted precisely. There are 2 basic types of crankshaft position sensors: magnetic and hall effect. The magnetic type uses a magnet to sense notches in the crankshaft. As notch passes underneath, it causes a charge in magnetic field that produces an alternating signal. You have to have bellhousing bolted on to hold it precisely in place. The magnet that you are using to hold in place, can counteract the sensor itself causing loss of spark badge714
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not sure how well that rigging job of the cps will work... thats the main reason you would not be getting spark

I also have the crankshaft sensor up near the flywheel with a magnet holding it on(since no tranny is in atm).

Click to expand...

Uhhhh.....that's probably why it won't start. The CPS is a magnetic pickup type sensor, so the magnet is probably keeping it from giving a signal.

Another reason might be the clutch switch, that keeps it from starting unless the clutch is depressed.......

Howdy,

Thanks folks. I've been out there and tested the ballast, it's fine. Got the cps up without magnet and still not working. Any other thoughts, I'll go mock it up better now.

Also will look into the clutch switch, but think I've already got it covered.

Flip

How much gap do you have on the crankshaft sensor. Do you have spark at coil wire, if so it could be camshaft sensor in the distributor. badge714

Hey badge,

I mocked the bellhousing up there with the CPS in it. Still giving me trouble. No spark to the coil wire.

I also have run the codes(check engine light) and come back with the following code set:

12 begin
11 cps code * that's while it's hooked up properly in the bellhousing
55 end codes

I'm gonna go check out that camshaft sensor, but with no spark at coil it seems the problem is elswhere.

Thanks for the replies, I'm at my wits end and all this help is greatly appreciated!

Flip

did you check the wire hareness at the crankshaft sensor, try wiggling the wire hareness at the crank sensor while cranking the engine badge714 give me a holler at [email protected]
have some trouble sheets but can't send thru forum

Thanks for the help badge.

Dark out now so I called it a day, just shot ya an email a few minutes ago. Really appreciate it.

Will try the harness tomorrow.

Flip

igniton module?