Can anyone shed some light on this problem? ... i bought a 95 blazer SLE from an old lady. It was her late husbands who passed some seven years back. And has set ever since. Now truck is a cream puff under all that tree mold and such ...but.... Some nice little rodents had made quite the mess of the wiring harness . Now i fixed all that,still no luck though ...long story short piece by piece it has a completely new fuel system and ignition system . Fuel pump,spyder injector , dist cap, rotor ,wires, plugs , ignition module, coil.. Still nothing. Im about ready to burn it. Now , i do have spark and i do have fuel , 60 psi, but my spyder is not spraying . I have 12 volts at the plug on spyder injector. Have even hooked it up with gator clips to battery , and if i manually break the ground circuit it will spray and ....'voila... Its alive.. My question is why it not pulsing on its own? Any one been through this befor?

 

check all you grounds. do u get dash lights?

 

Sorry I cant help with your question and hope your just kidding about the above quote but if match comes to gas please do a youtube of it

 

Again check the grounds as the PCM (engine computer) grounds the fuel injector in order to spray the fuel. Also check all the wiring once again for opens.

Good luck.

 

I believe all grounds are intact. At least that i could find and ive been into harness pretty deep now. I have even ran an extra from firewall to the post that the coil bolts on. All my lights work both inside and out along with dash lights and gauges... im thinking mayme the pcm itself?? I dont what else it could be. Someone said camshaft sensor, but it must b picking up signal since its has spark.? ... And yes firsttimer should it come to that, i will absolutly post the burning.lol

 

do you have a full wiring schematic? if all your grounds are good, check and grounds and voltage wires going into the pcm. also check check your ignition switch/icm

 

I have no schematic...other than a haynes book.. Which dosent really go far enough into it , it seems

 

swing past your local garage or dealership and see if they can print you one out. it may sound stupid, but with all the electronics and wiring on these trucks, a simple low voltage (like on my truck) or too much resistance in a ground, can cause a truck not to operate correctly.

 

I think you have the answer, the PCM. If all the wiring is good, the injector sprays when jumpered...then it must be the PCM since it provides the switch to fire the injector.

Check your local salvage yard for a used one, then try ebay.