Chevrolet Repair: ecm b fuse, chevy blazer, fuse box

Question
QUESTION: ok i have a 2001 chevy blazer 4.3 v6 .this all started when the catalitic converter stopped up on my way to work.i drilled a hole in it to get me to work and home.i then cut it off and replaced it with a straight pipe.i left all the o2 sensors in the exhaust pipe.after doing this i started haven probelms gettin fuel from pump.i have cked the fuse relay switch located in the fuse box under the hood and replaced it.didnt work.i started ckin fuses for power and realized the ecm b fuse had no power.i put a code reader on it and reset the ecm.it started and ran for 2 mins.i counted.then it died.i reset it again and it done it 2 more times.after i reset the ecm i had power at the ecm b fuse until the pos died.now i cant even get it to reset and get power to the ecm b fuse.ANY HELP GREATLY APPRECATED

ANSWER: HI JAMES,THERE IS NO SIMPLE ANSWER TO THIS ONE. THERE ARE SOME THINGS I WOULD CK HOWEVER,CK THE WIRING HARNESS FROM THE FUSE BOX TO PCM,WIGGLE ALL THE WIRES TO THIS PCM. THIS COULD BE A BAD OR SHORTED PCM..SORRY I I AM NOT ABLE TO HELP YOU OUT MORE,BUT THIS IS ONE OF THESES CARS THAT WOULD NEED TO TAKE SOME DIAGNOSTIC TIME TO TRACE. WHEN YOU HAD THE SCAN TOOL ON THIS DID YOU CK FOR ANY CODES IN SYSTEM BEFORE RESETTING THE PCM ??? THIS MAY LEAD YOU IN THE CORRECT AREA. IF YOU ARE NOT GETTING ANY READINGS FROM THE PCM MORE THEN LIKELY IT IS A BAD PCM.WHEN CRANKING ENG OVER SEE IF THERE IS ANY CRANK SIGNAL FROM PCM. ALSO CK FOR ANY 5 VOLT REFERENCE TO ANY OF THE SENSORS IAC,TPS. IF NOT WIRING PROBLEMS OR AGAIN PCM. THE FACT THAT AFTER YOU CLEARED IT AND IT RAN FOR A BIT SOUNDS LIKE AGAIN PCM. IF YOU CAN GET ME MORE INFO PLEASE DO SO. ALSO WHEN YOU LEAVE THIS SITE COULD YOU PLEASE RATE THIS QUESTION THIS WILL HELP ME, THANKS TOM.

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QUESTION: pcm ,hmmm
i thought about this but i didnt think it would be it seems i am able to reset evrything and it runs.there was no codes in the system.how do i ck crank signal?i havent started ckin volts on sensors,thats my next step.i have had some ppl tell me that the fuel pump is bad but i dont know because after i reset everything it runs for 2 mins.i plan on ckin the volts at the pump.also i was wonderin if it is possible to put a jumper wire in to get my ecm b fuse to stay hot in order to ck voltage?thanks again for ur response.

Answer
HI JAMES,I WOULD NOT RECOMM PUTTING A JUMPER WIRE IN THE FUSE SLOT,,NO NO NO..WHEN YOU SAY RESET DO YOU MEAN CLEARING THE PCM ???? GET YOUR SCAN TOOL AND USE THE DATA SIDE IF YOUR SCAN TOOL HAS THIS FUNCTION AND NOT JUST A CLEARING TOOL.ONCE YOU ARE IN THE DATA SIDE CRANK THE ENGINE OVER AND WATCH FOR CRANK SENSOR THERE SHOULD BE A READING HERE,IF NOT THERE IS EITHER NO SIGNAL FROM THE PCM OR SENSOR IS BAD..I HAVE SEEN CRANK SENSORS DO THIS,BUT WILL NOT BLOW A FUSE..THE ECM IS FOR ELECTRONIC CONTROL MODULE,ON THIS CAR IT IS NEXT TO THE COIL ON PASS SIDE OF ENG..THE PCM IS POWER CONTROL MODULE,THIS CONTROLS ALL OF THE SIGNALS TO THE ENGINE AND FUEL PUMP. I WOULD REMOVE THE WIRING HARNESS ONE AT A TIME TO COIL AND ECM AND CRANK THE ENGINE OVER TO SEE IF THE FUSE STILL POPS.IF THE FUSE DOES NOT POP PROBLEM IS IN THIS CIRCUIT..MAYBE YOU CAN GET TO THE SOURCE LIKE THIS. I WOULD HAVE TO LOOK AT A WIRING DIAGRAM TO SEE IF THE FUEL PUMP IS TIED INTO THE ECM SIDE ON THIS TRUCK. TRY TO REMOVE THE FUEL PUMP WIRE CLIP ON FRAME RAIL AND CRANK OVER TO SEE IF THE FUSE POPS. A FAULTY FUEL PUMP WILL POP A FUSE..LET ME KNOW IF MORE HELP IS NEEDED, TOM....