Ok so I am in the process of swapping out my TBI with a TPI in my 1990 camaro. Im using a TPI setup from a 1989 Trans am but in the process of getting my new wiring harness in, i see a plug for the 9th injector right where the 9th injector would be so this cannot be a harness from an 89. Is there any way to find out the exact year this harness is from?

Will this harness work if im using the computer and Prom and setup from an 89 Trans Am and not hooking up the 9th injector?

also, i dont have the fan wiring harness so do they differ? which one will i need?

also do any plugs differ from my TBI to TPI I have the TPS MAF and IAC all set.( i know both the fan relays and the fuel relay.) should i know about any other plugs that i might need to cut or make work?
Any help is greatly appreciated!

 

Same problem, I need a new harness to wire up my 91 Z28

 

Both of you would have an easier time with a 90-92 TPI harness. Plug and play with a wire or two to join, mostly for the speedo circuit

Older harnesses must be repinned to the 90-92 pinouts. The old stuff can be made to work, but its a good bit more effort

You're wasting your time reworking a TBI harness to TPI standards. A few sensor connectors are the same body, but the ECM is completely different and harness routing is completely off. For your specific instance, your 90 TBI will use the newer style TPS/IAC which isnt compatible with the 89 TPI. Your TBI harness wont have the necessary MAF connector either

Fan control can be independent of the stock harnesses if you chose, TPI doesnt have a specific circuit which only works with TPI

 

Right, I know I need that harness. The one I have now has melted connectors and hacked up wires from someone else's botched attempt. I'm really looking for an extra one thats floating around so I can finish my car.

Can someone take pictures of where the injector wires go and the vacuum lines?

 

I am using a TPI harness., not trying to make the TBI harness work. I have the TPI harness