Hey guys I have a 96 Blazer 4x4 with the 4.3 Vortec. Well anyways the problem I'm having is when I turn the key to the on position, I get no dash idiot lights, no gauge checks, no fuel pump prime. I already replaced the Fuel Pump, the ECM, the Ignition Coil pack, and the Battery. I checked for spark but also nothing. I noticed when I just bump over the starter real quick that then all the idiot lights come on and the fuel pump will then prime itself. CAN ANYONE PLEASE HELP ME??? I think I pulled out every last hair on my head. THANKS

 

Sounds like an ignition switch failure to me.

 

Where should I even start to check if it's the IGNITION SWITCH?????

 

You could start by taking a look at the link in the bottom of my signature. A search for "ignition+switch" will also give you some further information.

 

So I opened up the steering column and tapped on the ignition switch, then everything came on as it should. I then started it but it ran really rough for a minute or so then died. What do you think that could be?

 

Ignition switch... There are many contacts inside the switch that can fail. It typically is a domino effect.

 

Thanks swartlkk. Gonna go pick up a new switch and install it now. Will be back to let you know what happens. Thanks again.......

 

Alright so I replaced the Ignition Switch and now everything works as it should and it starts up fine, BUT.....it runs really rough then dies after a minute or so. I hooked up my code reader and got the code for Low voltage on the MAF and also the Crank Position Sensor. Any thoughts of what I should do next? Now I'm kinda lost.....

The only code I'm getting now is P0341.

 

P0341 - CMP (camshaft position) Sensor A Circuit Range/Performance

The CKP, CMP, and MAF are all fed off of the +5V reference from the PCM. The TPS, EGR and FTP are also fed off of this reference.

 

I just installed my old ECM and now its all fine. A tech at the local Chevy Dealership told me that the new reman ECMs need reprogramming before installation so instead I just thru in my old ECM since that wasn't the problem. Thanks for all the help swartlkk......