why is my truck not firing

Year make model plz

the ground connection of the 1/0 battery cable to the chassis ground should be wirebrushed clean...the battery should be younger than five years old...with the chassis ground with a reliable source (not varying amperage and voltage) your ECM has a shot at getting it right~

Ok first work smart not hard scan see if any codes, or no communication no communication... be sure you have a working obd 2 port if your rig had factory security, (ie) flashing window that says security constantly, take key to dealer or quaified locksmith to test key. This truck may have a skim reader,(the key sends a signal to truck,oh ok yup you are mine ill start. If this is the case the security light will have been acting up for awile annoying flashing, stalling ,and just generally irritating. Solution replace key w proper programming recommend the dealer the reason oe parts work better and are engineered for your ride,and will give you a longer service life, you get what you pay for. Test,test,test first

Hope that helps

the security light is not flashing. do you know what could be causing it to crank when its cold but starts to sputter and then shut off and will not crank again,seems like it loses spark.

Do you have communication to ecm when no spark condition exists? Check grounds on back of the head on drivers side

Wire can be broken or been pulled inside insulation cold the insulation will soften and stretch breaking connection cold it shinks making connection again

Also check coil packs.

the coil packs are good do you know if there is a ignition module or something that could cause it to lose fire and sputter

Ecm runs everything

Connect obd 2 tool and see if you have communication,no communication computer is toast

I have a GMC Sierra 1500 5.0 1995 and it will turn over but won't crank it's getting fire to the coil got me spark plugs and fuel filter what else could cause it not to get fire to the distributor or not crank?!?

New spark plugs and fuel filter**

Having same problem 05 Silverado 4.3 sputters when mouister in air or raining then just stopped firing completely any help would be great

My 96 4.3 was not starting when humid or raining outside took for ever to start and when it finally did i popped the hood while it was still dark out 5:30 goint to work and heard a ticking noise as if a spark plug wire was disconnected. Then tracked it down to the ignition coil it was sparking all over the place went bought a new one and never had that problen again

On an external coil pack,the coil wire post will make oxidation if aluminum/green if brass clean w a mild sandpaper,replace coil wire and use DIELECTRIC grease to prevent moisture and reoccurring issue I moist climates.

Got Chevrolet Silverado 1500 2000 v6 .I replaced a cap and rotor crank senson and can sense modern and distribution sensor. Not fired

I had this problem on my 2001 Silverado 4.3 changed ecm,icu coil plugs wires cap rotor battery ground wire fuel pump crank sensor and still no spark turned out to be a fuse for inj 1

I had the same problem on my 06 avalanche, turned out to be a ground wire behind the engine that wasn’t grounded, found it by accident lol