How to test a coil on the vehicle

If you suspect a possible bad coil, here is a quick and easy way to test the coil without expensive labscopes and equipment.

Category:

Autos & Vehicles

Tags:

• P0304
• cylinder
• #4
• misfire
• automotive
• diagnostics

[jcb1972]

That is some epic music at the end.

[frankie2234]

Great info. wish you were in the detroit area. Good mechanics (and honest) are hard to find.

[AreThereNoMoreNames]

Heh, we always just used to have the new guy hold the wire and watch to see if there was a spark.

[lightlyone]

Great music for this mechanical drama. At least it wasn't a Powerpoint lol. Good advice tho.

[seapeddler]

But, what is the spark plug wire resistance? I bought a set of Bosch premium plug wires and 1 wire measured 17 000 Ohms. So, getting a spark at the coil does not mean a strong spark reaches the plug. Weak sparks lead to quicker oil contamination, due to incomplete combustion. But, I really don't think this will affect the orbit of the moon. no wires connect moon to earth, yet.

[Elricck]

@txturtlelytiger lol

[jpinedo18]

Nice job men

[txturtlelytiger]

just get a TUNE UP YALL DUMB FOUNDED LAZY CITIZENS , ITS CALLED MAINTENENCE!

[johnybarcelona1]

Is it going to live or not???

[scaryclown34]

@ratrace2p51 a test light!!

[TheAuburnhighschool]

can that be done on GM cars?

[HOTRODRICO]

@lamilicia YES, THE COIL COMES AS A PACK.... 4 COILS PER PACK IN THIS CASE

[boaterbil]

@middimar test first! Lisen to the man talk.... need evidence!

[boaterbil]

@KrojinKin Perfectly safe. I have tested coils with a DMM and they checked out good. This test tells the story and the only way you will get shocked is if you dont ground the test light as stated

[lamilicia]

Hey realfixes.... in this case, do you have to chance the whole thing, I mean all 4 coils??

[ratrace2p51]

Ya know what? we need a series of videos that diagnose all of the sensors

on the engine. Ya know, the cam-position, Crank-position, IATemp, MAP, Throttle,

all of that stuff.

Then, do another engine build of a 4 cylinder.

That would cover 90 % of the cars on the road today.

I watch these videos over and over, they are like entertainment..

[ratrace2p51]

This guys is the best.

[ratrace2p51]

really like

what is that tool??

[ratrace2p51]

really like

[ratrace2p51]

so cool.................

[birlochas]

Good done, keep on going...

Fixing problems would be

easier if we had more people

like you explaining the procedures.

Thanks a lot.

[KrojinKin]

This is not safe, if you have a DMM you can check it correctly.

[blargblarghonk]

@EMPIRE0FLIES

It output's both but it uses really high voltage 15000-50000 in some cases to achieve spark in a high pressure environment. The amperage can be tested but I wouldn't count to much on it.

[dbest1a]

Thanks for the tip. Currently in a no spark situation in a 1997 ford ranger 2.3. Changed ecu/camshaft sensor n crnk sensor to still no spark. Plu coil packs.