I have a problem that i cannot find an answer to. my blazer dies randomly. it may run for minutes or days, then the engine dies like someone turned the key off. it always restarts the first time. recently it began having trouble starting after dying multiple times. it shows no trouble codes, no misfires, it just dies. i can feel it about to die while driving at highway speed because it will become unresponsive. i can give it full throttle and it will kick down and take off again, if i dont do anything it just dies. no stumble. no other warning. at idle it just dies. weather, temperature, time of day makes no difference. engine hot or cold makes no difference. i have been working with 3 master techs to get to the bottom of this and every part that has been replaced has been because something has rationally lead me to believe it needed replaced. here is my list for the past 2000 miles. i bought this thing not running.

fuel pump, PCV valve
plugs wires cap and rotor to drive it home
speed sensor for irratic speedometer
tps for jerking at highway speeds. replaced at same time as speed sensor
engine coolant temp sensor and pigtail
map sensor and pigtail
cleaned IAC and EGR. unplugging makes no difference in dying
PCM-no difference when swapped
ignition module-no difference.
fuel pump again, fuel filter again
FPR-ran fine for 200 miles then acted up again
spider injector-no change. no fuel puddles in intake
transmission solenoid kit. tranny suddenly lost first gear one morning. thought maybe lockup solenoid was acting up also. tranny ran fine afterwards.
removed dash and wiggled every wire on engine and on dash, including ignition switch with no change. removed all existing security system wires with no change.
gas analyzer shows exhaust at 17:1 and engine still runs great. except for the dying thing.
we are all out of ideas. we only have ignition switch, coil and CPS left unless someone can give me some insight. i now have $2200 invested total in this 4x4 so i am not upside down, just want to get it running perfect before i sell it. but on a lighter note, it is now under a full warranty!

 

Have you checked and/or replaced the wiring harness to the CPI injector inside the plenum?

 

i have wiggled it and unplugged it and plugged it in on 2 separate occasions. it looked fine both times i messed with it. its that 2 wire one that looks like the TBI injector connector. i will see if i can find a pigtail for it and solder it on. my experience is on Toyotas and suspension systems and gears. i was ASE master for 10 years until i let it expire. my help is a 15 year master that specializes in EVERYTHING-he grew up in a junkyard, the other is a 15 year master that teaches Vo Tech. and we ran out of ideas. neither of the them have messed with this truck, they are just there for me to bounce ideas off of. so any outside help is very appreciated.

 

ok i replaced the wires going to the spider injector about a month ago then loaned the blazer to someone who needed a vehicle. it is still dying and seems to be surging at highway speeds and trying to die. any other suggestions?

 

i replaced the coil the other day when it wouldnt start. of course when i got there it started just fine. a week later it wouldnt start for the driver, then started the next day but not for the rest of the week. went over today and it started on wd40 (the only flammable item i had on hand). so i figured either the CPS or who knows what. i couldnt hear the injector tick when unplugging the cps so i thought maybe the spider injector again. i found a small section of wire on the harness side of the injector connector that was not shaped right. i corrected it and it started. so i bypassed the connector and replaced the damaged wire (the kind where the wire is broken but the casing is intact). havent had any problems since, so cross your fingers with me!