How to determine if all cylinders are firing.

[spikoman69]

How can I determine if all 6 cylinders on my Jeep Cherokee are firing??

 

[philbar71]

listen to it. and also look at spark plugs if they are coverd in gas then the plug anit firing.(works on a lawnmoer)

 

[CrazeD]

Pull a plug wire off while it's running and see if the tune changes.

 

[Harper]

listen to it.
You will noticed a drop in your vehicals performance.

I had some simulare issues with my car doing that 2 weeks ago.

 

[spikoman69]

Will the check engine light come on if they all arent firing?

 

[lancec2c30]

Well, it depends on how advanced your ECU is in your vehicle. The check engine light may come on. But if the vehicle is older it won't.

There are a few ways to check if you have mis-firing cylinders.

Pull all the sparkplugs and see if any of them are out of the norm, you will be able to tell the bad one apart from the rest by looking at the color.

If you have a temperature gun you just let the vehicle warm up to operating temp. then take a temp reading of each exhaust manifold exit from the head. The mis-firing cylinder will be much colder.

 

[thirdshiftdj]

usually it will idle pretty rough. I took two ignition wires off once and forgot to plug them back in and went to start it up and it was idling real bad like it was about to die.

 

[C0RR0SIVE]

Depending on if your car has OBD or OBD2 your computer will tell you if it is misfiring, or which cylinders are misfiring... Easiest way if it isn't reporting anything is to buy a little device that hooks up to the plug and the wire in the middle, that way you can see the spark, just to make sure that your distributor, or the coil pack is sending a spark out or that your wires are good... Also check each plug, if any of them look discolored or damaged and what not, replace the set. Plugs don't cost to much.

 

[superdave1984]

Yeah pull off a plug wire with it running. You'll get a nice shock. If you have a timing light you can put the connector on each wire to see if it is getting a spark to it. If spark is getting to the plug that's half the battle. If you remove the plug and it is covered with gunk, it is either not firing or you have a lot of blow-by fouling the plug. If you have an extra plug you can install it and leave the old one in the wire then start the engine. You should be able to see a good spark. If not, replace the plug if you know the plug wire is good.

 

[Harper]

Will the check engine light come on if they all arent firing?

It did on my car