Sounds like 'limp in' mode to me. I suggest you pull the codes.

There ARE connections to dash harnesses in most OBD I systems but they are mainly power and of course the SES light, as well as brake sw. Oh and .. Probably...VSS.

 

there are no codes no engine lights on. runs idles that harness is a 91 4.3 harness coming out the firewall to the motor only the dash is still 87 that connector i spliced in to get power to the injectors but also my tach and coolent gages dont work but oil gas and battery do. it kinda feels like a tractor it should have the power to spin the wheels if u tried but from driving it you knew it wouldnt lol

 

Does SES {check engine} light come on when key on? How do you know you have no codes?

 

u kno im really not sure i will check tomorrow i just assumed because the engine light was not on. so if the engine light does not come on with key on then what would that tell me?

 

so no engine light aluminated when key on, actually the only dash light that comes on is just the battery light. so what does this mean?

 

It means you have no idea if the pcm has codes or not. And it might be that you need it to read out those codes too, I dont know.. cuz I dont have the diags for either model

 

gotchya well im going to trace down some wires i believe are connected to that. even if i dont have a engine light wired up or what ever can i still pull the codes if they are in the computer?

well no that wont work i gota get that light to come on to read the flashes

jumped brown and white stripes together and got the engine light to come on with key on and goes out when running. so still think i have codes?

 

You still might. And they could be relevant, so read em anyway.
Check timing and fuel pressure. Check your EGR system

BUT PLEASE use instead of posting each thought separately. No I am not a mod but I used to be, elsewhere.
There's no lollipops for post count..
though you DO get one for figuring out the wiring.

Believe me what you are learning/doing now will probably come in handy in the future, not just for this project.
I did several EFI engine/pcm transplants and that's how I know.

 

sounds good i was just trying to get some replys alittle faster but im going to read some codes and what not and check the egr valve and solenoid. will keep updated and thanks i'll be waiting for my lilpop haha

 

pulled code 24 vss looks like i got another puzzle to figure out im not sure if you can use a 2.8 vss buffer with a 4.3 or do i need a computer out of a 88 instead of a 91?. if anyone knows some info on the vss system please let me kno thanks