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PanPan
Jun 21, 2010, 06:23 PM
How do I test my GMC Jimmy to see if the spark plug is getting a spark. My Dad used a screw driver and said it wasn't getting a spark. Is that possible to do?

Stratmando
Jun 21, 2010, 06:30 PM
A screwdriver placed correctly, with a gap can show a spark.
What I tell someone that says it has no spark, is to hold on to it while cranking, if they won't, it may have spark. I learned from an old tech who said to prove it out. If checking a plug wire, rotor or cap could be bad, a test on coil wire may be better.
Because it doen't fire doesn't mean the coil is bad, could lack power to the coil.
What year and Engine size?

TxGreaseMonkey
Jun 21, 2010, 06:59 PM
Spark Test. Remove a spark plug wire and attach it to a properly gapped spark plug, touch the plug to a convenient ground, and observe the spark, while someone cranks the engine. Look for a good, solid spark.

It's common for the Ignition Control Module (ICM) to fail, which can cause it to not spark or to spark at the wrong time. Heat destroys the microchip inside.

This link may help:

https://www.askmehelpdesk.com/cars-trucks/faq-how-troubleshoot-repair-maintain-hondas-selected-other-vehicles-46563-11.html#post2123675