No Start issue is looking like the pick up coil in the dist.

Does the dist need to be removed in order to change the pick up? looks like I can get to everything from top, although a little tight. I've done most of the tests from ignition switch down line. I've installed new amp module, checked coil, cap, rotor, wires, all looks good.

Thanks in advance.

Don Cookson 1987 XJ6 4.2

 

OK, its a Series 3, so as I remember it, the top of the distributor is fairly easy to access, although its obviously easier out on the bench.

Doug Dwyer is our resident mine of information on these cars, but you'll be better off posting this on the XJ6 Series 1, 2 & 3 forum, because he looks in there a lot. If you suspect the reluctor coil have you tested for getting a pulse ? I think you do need fairly sensitive equipment to pick this pulse up, hence Lucas putting an amplifer in before it gets to the coil.

 

thank you fraser, I've noticed Doug is the man out there helping all of us with XJ6's. Most of the information and tips I've found are from Doug. Still working on the car and no spark but on the path to getting it fired up.

FYI, My grandfather was from Leeds England, I think the attraction to Jaguar is more than physical. Must be DNA.

 

A bit foggy on this...it''s been years....but I don't think the distributor needs to be removed. Give it a whrl. If I'm wrong the worst that can happen is that you DO need to remove it....which is no big deal.


Cheers
DD

 

OK, replaced the pick-up coil in the distributor. no problems just a few screws and a light modification to the wiring shroud that fits in the notch of the distributer. I did not replace the plate, only the pick-up and wiring. Still no spark!! I did replace the module in the amplifier (GM part) wiring seems to be fine and I do have 12V at coil. No spark out of the coil? I will replace the coil and do away with the resistor thanks to a post regarding "ballast resistor"

One article on the "NO Start" problem ended in success with replacement of ignition switch. Could that be the problem even with power to the coil?

Also noticed no change in voltage from voltage gauge in dash, as in not working, no movement with key on or at start. Any relation to my no spark?

Thanks again for all your great advise.

Don Cookson - Bonney Lake, WA.
87 XJ6 4.2

 

The coil is the only thing left as far a components go. But "seems fine" isn't good enough as far as wiring goes :-)

The wiring takes a beating over the years and the small harnesses to-and-from the ignition module are always suspect....although in replacing your pick-up coil you also replaced half the wiring, leaving you with only the amp-to-coil wires to double check.





If the coil is getting "key on" voltage the ignition switch is doing at least part of it's job. Makes SURE, though, that this "key on" voltage supply to the coil is also present with the the key turned to "start" !

An easy check is to simply run a jumper wire from the battery "+" post to the coil "+" post and see if anything changes




No relation that I can think of.


Here a "CEI" checklist out of the Jaguar service manual. Might help.

1) Measure voltage at coil "+" terminal with key "on". It should be within
one volt of battery voltage. If not suspect a problem with the wiring to the
ignition switch, or the switch itself.

2) Measure voltage at the coil "-" terminal. Result should be the same as at
the "+" terminal. If Ok, go to step 3. If not....
Disconnect the wire from the amplifier from the "-" post of the coil and
measure voltage again. Less than 2 volts means the coil is faulty. More than
2 volts means the amplifier is faulty.

3) Disconnect distributor pickup coil from the amplifier (this is the
harness from the distributor that plugs into the amp). Measure resistance
across the terminals. It should be 2.2k to 4.8k ohms. If Ok, go to step 4.
If not, replace the pickup.

4) Reconnect the pickup to the amplifier. Measure voltage at coil "-" post
while cranking engine. The voltage should drop. If OK, go to step 5. If
not, the amplifier is faulty.

5) Check distributor cap and wires, distributor rotor arm, spark plugs, coil
wire




Cheers
DD

 

Thanks again Doug, you are my hero. although the car is not running yet, I've noticed a small fracture in the "Amp to Coil" wire. the wire is still in tact but frayed. I will repair and also do the tests you provided. actually thought about replacing the complete amp box. found one on ebay. might install new coil and see what happens. I will spend more time on wiring as well.

If we ever cross paths, A PINT or two are on me.
Thanks for all you do.

Don