I have a 91 RS that I swapped an 87 305 TPI into and it wont start. I swapped over the engine and dash harness so I wouldnt have to mess with pinouts. I do not have all my sensors hooked up but I dont think that is my issue. Are any of the sensors essential to the car starting? Also while it is cranking over I get smoke from the negative battery cable. Help!

 

ok I just tightend down the negative cable and its not smoking anymore but now the positive terminal on the battery is hot is that because its not tight?

 

Possibly.
What sensors do you not have hooked up?That could be the reason it won't start.

 

the knock sensor, temp sensor (on the driver side head), oil pressure (by the oil filter) are not hooked up cause they are broken.

 

I'm pretty sure the knock sensor and oil pressure sensor need to be hooked up,the temp sensor on the drivers side head I believe just sends info to the gauge itself and shouldn't effect the ecm
also,is this a complete engine swap or just the tpi swap?
If you swapped tpi intake onto a tbi engine,you got the wrong knock sensor on there.

 

Black Ice, You need to hook up the oil pressure switch (the one near the filter). If this switch is not hooked up your fuel pump will not run. It will only prime when you initially turn the key. That is unless you have it wired up differently. -Bob

 

TIMMYS89GTA- This is a comlete motor swap out of a running 87 Iroc all wiring also came from the iroc

Egg83- It is not wired differently however I still do not hear my fuel pump at all when I turn the key

I will try to get the knock sensor and oil pressure sensors hooked up and see if it helps any

 

You obviously have a problem with the fuel pump circuit. I can't spout details, but the oil pressure switch is not the primary circuit, the fuel pump relay is.

 

five7kid- I also have no spark at my plug wires leading me to belive that the problem is bigger than just the fuel system

Is it possible that somthing in the body wiring that had to be adapted from 91 to 87 stuff is causing my issue?

 

Sure sounds like it. Again, I can't provide details, but such problems sound familiar.

 

You should never try to go backwards with electical. An '87 uses two wire harnesses, the '91 has everything in one. That's under the hood anyway.

 

dyno don- Not sure what you mean by 87 having two harnesses under the hood? I pulled 1 out of my 91 under the hood and pulled 1 out of my 87 under the hood. The only challenge in the wiring swap was adapting the 87 dash harness to the rest of the 91 body wiring (lights-gauges-ect.)

 

Woo-Hoo! It lives! I just had the two pigtail conectors by the battery backwards. Thanx for all your advice guys im sure I will be needing more in the near future...

Now off to get those sensors lol

 

good luck with it!