Sub Zero Starting System
 

Hello all. I am in the process of swapping engines between an 89' and a 91'. When taking the engines out we noticed that the 89' had what we found out to be a Sub-zero starting system that our two 91's didn't have. Is this something that is necessary? I assume it helps starting in cold weather but why was it removed in the 91' model?
Thanks

It is an ether injector to make the fuel more explosive when its cold. They removed it since it was actually a REALLY bad thing for the engine and they found most people who use this car don't live in sub-zero conditions. Also I think by the time 91 came around they had refined the car to the point that it was far more reliable than the previous years.

So long story short... unless you are in Minnesota in the winter with the car, you don't really need it. Just make sure your battery is powerful and your fuel system is cleaned and in good working shape. If you have the injectors out I highly recommend getting them cleaned and balanced and also replacing the air bleed socket o-rings also the injector o-rings. Make sure that your fuel pulsation dampener isn't leaky. It is just a thing I have since I have read lots of "leaky injector" posts that end up causing flooding issues and leaky pulsation dampeners that cause fires.

Relocate the whole system to the garage floor where it belongs. You can get a blockoff plate for the spot where the injector mounts on the intake manifold. I believe there was a TSB to have it removed from all cars, I don't think it even does anything.

Like he ^ said.