I recently purchased a 99 Blazer that had a starter issue. I replaced the starter and it started fine and ran fine. The Blazer sat for a few weeks waiting to get money to register it. After registering it tried to start it and it won't start. Have gone through a **** ton of troubleshooting. First checked for spark and it is getting spark. Fuel pump is working and maintains 60psi until cranking, it drops to about 52psi when cranking.

 

You must have a good blue, not orange, spark at each plug. Try a shot of carb cleaner in the intake, if it starts and stalls, check fuel pressure and leakdown. On 1998 and newer, in the underhood fuse panel there is a vacant terminal next to the fuel pump relay. This is the "fuel pump prime terminal" and it goes directly to the fuel pump. Connect a jumper wire from battery positive to the terminal. After the fuel pressure stabilizes, it must be 60psi to 66psi. Then remove the jumper wire and the fuel pressure must remain above 55psi for at least 10 minutes. If it fails either or both parts of the test, there is a problem with fuel delivery and further testing is required to pinpoint the problem. Post your results.

 

Well I had no leak down on the fuel system, already checked that. I am thinking it might a problem with spark then. I have spark, but it is not a pretty blue though. It has been rainy and really humid here as of late. Could be moisture in the sytem?

I also dumped some gas down the throttle body this morning and it didn't start. But, it did did try to run after I let off the key from cranking it.

 

Distributor cap, rotor, wires and ignition coil are all common places to "leak" spark. AC Delco only for the cap & rotor, don't waste your time or money on anything else.

 

Finally got a chance to work on the Blazer again. Replaced the cap and rotor, then tried to start it. Started up right away but has a miss, so I'm going to assume some of the wires are bad also. Next chance I get will replace plugs and wires.

 

Make sure the cap is wired correctly. Common mistake to transpose the wires for #1 and #3:

 

if you replace the wires and still a problem, check the coil
A good way to check the wires is when its dark, take a spray bottle, on the mist setting, and lightly spray the wires, see if you can see any sparking

 

The cap is wired correctly... Made sure all wires stayed in order when I pulled them off.

I already got the plugs and wires. Just wanted to see if it would start with just replacing cap and rotor. Figured if the cap and rotor were bad the plugs and wires would need replacing also.