Chevrolet Repair: 95 blazer trouble, mass air flow sensor, little black boxes

Question
Hi,
   I have just bought a 95 blazer with the 4.3 vortec engine. When I drive it for more than say 8 or 10 miles it acts like the timing has jumped, it will idle really rough and stall out when in try to take off from a stop. I have replaced the egr, and ALL the little black boxes on top of the intake, I can't think of all their names lol. I have even put a new fuel regulator on the spider injection. I'm hoping it's not the Injectors, I can't afford that..... And last night I drove  around for a while and when I get back I turned it off and tried not start it back and it clicked like if the battery cable was loose but it was tight. Do you think all my problems could be from a bad ground somewhere?

Answer
HI CHARLIE,,WELL IT IS POSSIBLE THAT YOU ARE LOOSING BATTERY VOLTAGE CAUSING THE POOR RUNNING CONDITIONS. YOU WILL NEED TO START OUT AT FIRST BASE, FIND THE CAUSE OF THE LOW BATTERY IF IT IS LOW OR A BAD CONNECTION AT THE BATTERY POST. REMOVE THE CABLES AND CLEAN IF NEED BE AND RE-CONNECT THEM..NOW GET A VOLT METER  AND CK FOR 12 VOLTS AT THE BATTERY,IF OVER 12 VOLTS SEE IF IT WILL START. IF NOT, MORE THEN LIKELY WILL NEED TO BE JUMPED OR CHARGED. CAN YOU DO THIS ???
ONCE ENG IS RUNNING HOOK THAT VOLT METER UP AGAIN AND MAKE SURE THE VOLTAGE IS 13.8 TO 14.5 VOLTS OR IN THIS AREA WHILE RUNNING WITH THE LIGHTS ON,HOLD THE RPM AROUND 1500 OR SO TO CK THE ALT OUTPUT..IF THIS IS NOT CHARGING TO THE ABOVE SPECS LIKE LETS SAY LOW VOLTAGE UNDER 13 VOLTS THE ALT IS NO GOOD. BUT LETS SAY IT IS CHARGING GOOD. THEN YOU MAY HAVE A WEAK BATTERY WHICH SHOULD BE TESTED AT A SHOP OR PARTS STORE..HOWEVER IF THE BATTERY IS WEAK THIS WILL NOT CAUSE YOUR PROBLEM WITH POOR RUNNING, [[ONLY A LOW CHARGING ALTERNATOR WILL CAUSE THIS]].THIS IS IMPORTANT..OK SO LETS SAY CHARGING SYSTEM IS GOOD NOW AND BATTERY IS GOOD, BUT THE ENG IS STILL RUNNING POORLY. THE WAY YOU HAVE EXPLAINED THE PROBLEM IT COULD BE A BAD MASS AIR FLOW SENSOR..REMOVE THE WIRE CONNECTION TO IT AND SEE IF IT RUNS BETTER...[[[BETTER NOT PERFECT]]]IF IT RUNS BETTER MORE THEN LIKELY THE MASS AIR FLOW IS FAULTY. IF THIS HAPPENS ONLY WHEN IT GETS WARMED UP THE SECOND PROBLEM COULD BE A BAD IGN MODULE OR MAIN COIL..WHEN IT STALLS OUT I WILL ASSUME IT WILL START BACK UP..THE COIL ON THE INTAKE COULD CAUSE THIS [WEAK SPARK] WHEN HOT..THIS SHOULD KEEP YOU BUSY FOR AWHILE LET ME KNOW HOW YOU MAKE OUT AND GET BACK TO ME ON WHAT YOU HAVE OR HAVE NOT FOUND...GOOD LUCK,,,TOM...