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Let's check for spark - How??
- Thread starter XJ-wrecks
- Start date
RichP
NAXJA Forum User
- Location
- Effort, Pa
XJ-wrecks said:
Saw that question on another post and man that is a good question. Jneary is a jeep mech for Jeep, hopefully he will respond.... As for me, I don't know how you would do it except for maybe a meter on the wire....
Osprey413
NAXJA Forum User
- Location
- Dallas, TX
If you just ground the sparkplug to the block (pretty much anywhere) and crank the Jeep you should be able to see a spark. Atleast that's how I did it. Oh yea, just in case you didn't know, the spark plug grounds to the block through the outside threads.
jldiaz
NAXJA Forum User
- Location
- Caracas, Venezuela, S.A.
On the coil rail connector, the dark green wire with orange stripes should read between 0.71 and 0.88 Ohms against the oher three wires (check them at the connector, engine cold) when unplugged.
This, however, only tests the coil primaries.
If these readings are OK, It would be very unlikely for all three coils to fail at the same time. If any one coil fails, you will get a steady misfire on two cylinders.
This, however, only tests the coil primaries.
If these readings are OK, It would be very unlikely for all three coils to fail at the same time. If any one coil fails, you will get a steady misfire on two cylinders.
Last edited:
Matthew Currie
NAXJA Member #760
- Location
- Vermont, land of big clay
For really dependable spark testing, get a known good spark plug (old used one is fine as long as it sparks) and use a little hose clamp to attach a piece of wire with an alligator clip on it to the threads. Now you can plug a plug wire to that plug, and not worry about whether it was really touching ground, and not worry about getting jolted.
RichP
NAXJA Forum User
- Location
- Effort, Pa
We are NOT talking about the distributor type here, this is the rail mounted ignition system with the two plugs per coil. There is no 'taking it out and laying it agains the block' on this type so keep that in mind.
Matthew Currie
NAXJA Member #760
- Location
- Vermont, land of big clay
RichP said:
I haven't looked closely at this, but if they provide any reasonable way of removing the coil from the plugs to replace the plugs, then couldn't you make up a couple of test plugs, pull the coil off the plugs in the engine, and attach it to the test plugs?
jldiaz
NAXJA Forum User
- Location
- Caracas, Venezuela, S.A.
Following Matthew: Using three plugs on the rail (positioned one per coil.) and grounding them by clamping a wire to the threads, you'd have a reasonable test and not fry the coils.
