Hey everyone....Been a while but here it goes. On 12/12/15, I parked the Jimmy and disconnected the battery to avoid the alarm from going off or running down the battery as I normally do. I just went out there today to reconnect it and start it up but no luck. While I have had a rare case of hesitation while the truck was starting when cold never have I had a no start like this except for when the fuel pump failed several years ago but it appears this is not the case. Here is what I got:

-Truck has power, battery is new.
-No corrosion on battery terminals or cables. I even cleaned those up with a wire brush carefully before reconnecting them
-Starter and engine turns over without a problem
-Fuel pump hums normally when key is switched on and during cranking. It was just replaced a few years ago.
-Cap and rotor were replaced last year but when I pulled it it had green corrosion on the tips of the caps. I have wirebrushed the tips of the rotor and cap to clean it up and put it back together but still no start.
-Hoses were replaced a few days before I left and I believe there may have been antifreeze spilled on the cap based on the location of the heater hoses.

I have ordered a new cap and rotor anyway based on the repeat corrosion issues with this truck to see if there was a failure. Could there possibly be an issue with the computer portion on the battery reconnect? I am open to any other suggestions to try to get this thing running again because I am at a loss and this truck needs to be moved.... Thanks

 

There are fuse under the hood you should check ecm 1 and ecm 2 I believe. anyone correct me if I`m wrong

 

Another couple of things maybe your problem.The coil or Ecm Engine control module.
The ECm is the brain of the matter.The coil keeps things lit up.You can test the coil, or just replace it while your doing the wires and plugs.If the ECM is original that came with the truck?I would just replace it.Both of these aren`t that expensive, just a liitle more insurance on keeping a piece of mind.

 

Hey there computernerdbd, Start with the basics. Check for spark to the plugs. You say you can hear the fuel pump running so I think it would be safe to rule that out. Even if you have spark it could still be a bad ignition module. Here's why. My son had an '89 Sierra that had the same problem after sitting for a couple of weeks. turned out the ignition module was bad. Even though it had spark and the fuel pump was working, it had no fuel at the throttle body injectors. Turns out the ignition module not only controls the spark but it also signals the computer to inject fuel. Weird but true. So if you pull the air cleaner and crank it over and are not getting an injector pulse, go for the ignition module.

 

Do you have that Delco security system?

 

Ok thanks for the tips I checked all fuses and found no problems. I do have an aftermarket alarm which only kills the starter. Never have I seen the Security light so maybe that was already disabled.... Had to cut the siren wires since I did this at night and did not want reconnecting the battery to wake up the neighbors. I will splice them when all is said and done. Funny thing was either everything dried up enough or replacing the cap and rotor did the trick. It started up with a brief gas smell but ran without issue for my 6 mile test drive. I guess at this point monitor and be ready to change the coil or ICM if that happens again?