So I have finally got most of the wiring done on the car but somewhere down the line I must have missed something. The original Vats from my 91 RS seems to be activated at the ignition... As soon as the keys are placed in the ignition and I turn the key over VATS starts to flash and will make all lights inside flash as well. I was told I may have to bypass the VATS Module that is located under the dash, is this true? IF not what is it that I am missing? Right now I just need to splice in my Tach, spedo, and other gauges.. Any help is greatly appreciated, the rest is done its just this last step to be able to turn it on from the ignition.

 

A little more info might help
What year LT1 engine?
What LT1 ECM/PCM?
What harness ?
How have you integrated the LT1 wiring into the '91 harness ?
Standalone harness ?

Not as such.
You either use resistors under the steering column to "fool" the module into thinking the correct key is being used
or you get VATS deleted out of the tune and bypass the starter enable relay

 

Simply having it tuned out of the computer will not help him as he says the problem is with his original VATS box that is still in the car and not with the LT1 computer. You can bypass the VATS box in the drivers side kick panel with a few easy steps. Here is a post from pocket that describes it at the end of the post: https://www.thirdgen.org/forums/post...01-post17.html

 

Should do because it will allow the fuel injectors to pulse.
I assume he is smart enough to know the starter enable relay needs to be bypassed when doing a VATS delete.

So if as you surmise, his LT1 computer is functional then he has other problems causing his flashing lights (his VATS light could be on because of independent faults in VATS system )
So it makes no difference if the 91 VATS module is working or not , or even installed in the car because the module only supplies a fuel enable signal to the ECM and operates the starter relay.
Has no effect on anything else

 

The LT1 computer having VATS will not make the light on the dash flash as the computer should not be hooked up to the 91 VATS system in any way. I have never heard of anyone hooking up the LT1 VATS anyway as depending on what year car the engine is from the VATS could be part of the BCM. If his light is flashing there is a problem with the 91 system. Some people including myself have had to bypass the box when doing an LT1 swap. I had to bypass it on my car when it had an LT1, but didn't when I put an LT1 in my dads car. Also I am not saying that he does not have a problem with the LT1 computer but the case he describes starts with the 91 stuff.

 

Vetteoz-
Setup is an 95 LT1 with harness all came from a 95 LT1 Pontiac Trans Am, the LT1 PCM has already been tuned by Soloman and has no VATS. My problem is with the Car and ITS VATS. The harness is pretty much stand alone as it is only to run the LT1 and i will be splicing in to the C100 connector for instrumental cluster gauges.

If I use a tester and apply power to starter on the front of the car the Engine fires right up, as soon as I go inside and simply turn the key forward the SECURITY light flashes and will not go away, before I began my swap I had no problem.

 

If the vats is already programed out of the PCM jumper the starter enable relay under your driver side kick panel.

 

By-pass the VATS in the car. There are a couple of tech articles on it linked from the thirdgen.org homepage.

 

YES!! This is exactly what I was looking for, just as you mentioned this is what I have to do to bypass it. I also have not heard of anyone who combines the LT1 with the original VATS ???

 

Thanks to you all.... I knew it couldnt be that difficult, I mean afterall the hardest part is already done right? now to get it smogged with the State Referee.

rickyzZ28
Tuned Performance
five7kid

 

Hopefully the hardest part isn't still ahead of you...