Plug 1 and 4 issues - not triggering timing light

[bairohio]

Plugs 1 and 4 are not triggering timing light. When pulling plug wires at distributor I see spark from distributor to wire. Still though, these 2 do not trigger the timing light.

When i pull either #1 or #4 wires there is no difference in engine.

Car starts very easily. It just appears to me that I may be running on 2 cylinders.

Thoughts, suggestions?

I searched this site but was unable to see anything on this.

Fiat 2000, 1980 Carb

[JerryH]

Your wire might be arcing to directly to the engine block. Are the wires worn?

Pull the #1 or #4 wires off the spark plug and hold that end close to the block and see if you get an arc to the block.

Or better yet, pull one of the spark plugs and hold the plug threads to the block and see if you get a spark across the plug gap. Careful! Don't zap yourself!

[So Cal Mark]

wrong firing order

[bairohio]

Got it to register on triggering light but....

it appears that there is no difference in performance with 1 and 4 completely disconnected.

I have a 2 cylinder fiat..sigh...

any ideas on what the culprit might be here? If anyone lives near columbus ohio I'd be happy to pay for your time if you could come take a look as well.

[RRoller123]

As Mark said, make sure that you check that you have the firing order properly set up.

[GeorgeT]

I didn't see where you checked the plug wires themselves. Swap the #2 and #4 wires and seen if there is any difference.

[131]

As Mark said, make sure that you check that you have the firing order properly set up.

That's not going to affect the timing light. Either the spark is too weak to trigger the timing light, or it's non existent.

[bairohio]

They are in correct order from distributor to numbered spark plug. If I pull 1 and 4 I can see an arc at the distributor but it still has no effect on engine performance. Could the distributor itself be bad?


i tried moving wire as mentioned above. It would not start afterwards so I put back.

[131]

If I pull 1 and 4 I can see an arc at the distributor but it still has no effect on engine performance.

Do you have spark at the other end of the lead if you pull it off the plug? If you have spark at the distributor end, but not the plug end, replace the leads.

i tried moving wire as mentioned above. It would not start afterwards so I put back.

Did you swap both ends of the leads?