I have a 2000 4x4 2dr, I just replaced my O2 sensors, fuel pump, and fuel wiring and it was running fine. I still was pulling a code for my Cat though.

Today we had switched it into 4x4 mode, to get through a big mud puddle and within 40 seconds, parked and switched back to 2wd. Then about 20-30 seconds down the road the engine completely dies, i lose power steering, and brakes were very weak to stop us. My low gas light comes on (i have half a tank), my engine light starts flashing really fast, my 4x4 light comes on, and some weird noise comes from under the hood. It starts to crank but wont fire up. I cant hear the fuel pump priming any more and when i went out with my OBD2 to pull codes for the new engine flash, it wont even connect to the computer so i cant. Whats going on?

 

Loose connection to the PCM is my 1st choice. That &/or a connection to the fuse box under the hood.

Something isn't connecting as it should with the PCM or BCM. Loose or corroded or in the interior, could be ignition switch related. Look up Swartlkk & in his sig you'll find https://blazerforum.com/forum/2nd-ge...em-here-14727/ for ignition switch issues.

 

sounds like a problem with the pcm

check the connections they might of got loose

 

Thanks John lol... how long are you going to keep that green dot for this time?

 

I suspect under the hood. Look for drenched connectors.
I'm thinking something was hot and cooled too quickly, shorted out VRef.

Could even be in the alternator if your bat voltage isnt reading right.

 

Alright, thanks, ill start diagnosing as best as i can starting with the pcm.

 

Ok, so i found the ECM-B fuse was blown so i replaced it. When i looked at my dash, all the same lights came up. I cranked it over and of course it didnt start. I checked the new fuse and now its blown to. What should i do now? I have no experience working with control modules.

 

check the harness to all the sensors in the engine bay

a friend of mine had this problem with the fuse blowing while cranking and he had melted wires in the engine bay

 

Ive been really busy lately, but got out there today to check my wiring, and it all seems fine. Im still having the same lights pop up and flicker.

 

pulled out the PCM to test the fuse.
When PCM is in, the fuse will blow on start up,
When PCM is out, fuse will not blow.
??