87 s10 blazer 2.8 5 speed. swapped to 93 4.3 with 94 nv3500 5 speed. Got the whole swap done and finished and cant seem to get the injectors to power. i tested my dads s10 to see how they should test out and they are not the same. with the key off my dads s10 has power to white and red wires. and nothing on green and blue. hit the key on and the power cuts out to the white and the red and pulsates on the green and blue. obviously working.. well mine will have a weak light on white and red wires but when i get the test light to light up you can hear a relay clicking in and then no light. so i must be loosing power somewhere or somthing. iv been messing around with this swap for sometime so if anybody has any suggestions ect ect would be greatly appreciated. also i can give more info if i left some out Thankss

checked for power and ground at relay with relay out i have power and two grounds missing ground from the green and white wires. swapped in the working 2.8 computer to see if it would fix it but it didnt. iv torn the whole wiring harness apart and checked for bad wires, cant seem to find any. hope someone can help figure this out or at least help. thanks

The swapped engine ran fine before? Could be a problem with the distributor. I think I read before that these are negatively fired fuel injectors. So something in the system is not allowing or telling the injectors to fire. Will it run if you use starting fluid or gas directly?

yes will run if i manually put fuel into the tbi. i have fuel up in the tbi and the pressure also the motor did run in the donor truck.

also i checked for power and ground at the orange wire for the computer which i have power there but no power with the key on at the black and pink wire

i think i am missing a harness that plugs in the main harness right under the computer and runs over above the hood release i believe. anybody know what this does also it connects my pink and black wire that goes to the injectors, so that is why i do not have pulse

what is this plug?


http://i1106.photobucket.com/albums/...ap/harness.jpg

jumping the black and pink wire to ignition 12 volt source with 10 amp fuse actived them with no problem here is a diagram to help others out with some tricky but simple wiring.

https://blazerforum.com/forum/[IMG]h...ctorWiring.jpghttp://i1106.photobucket.com/albums/...ctorWiring.jpg

So it's up and running now?

yes sir, when i pulled the harness i pulled the engine only. there is one that plugs into the plug that i pictured above and basically is the whole dash wiring harness. so i just did some research looking everywhere and thats what i came up with. and once i turned it over and it had fuel coming out i knew it would start and it did lol.

Least you got it figured out. Was the 2.8 carb'd?

nope the 2.8 was tbi injection. but nothing was close to the same so new harness and everything else lol

would anyone know if i have to go get the whole internal harness? the truck runs and drives but does not have good acceleration it will get up to any speed just slowly.