89 4Mula 350 Tbi

Ok guys i have an 89 formula tbi with vats. Now my question is what does vats exactly do and disable .The reason i'm askin this is because sometimes i'll go to start my car and nothing will happen the fuel pump still primes but the car does not crank, but everything shuts off as if the car were to crank example the radio. Also i have eldelbrock headers that are really close to the strarter so i dont know if it can be the starter or vats because this morning the car wouldnt start but then i opened the hood and was going to try and bang the starter but as we know theres no room so i gave the key one more try and it strated. Also if you guys think its vats how do i disable it cause i dont want to spend 40 bucks on a new key.

joker37

VATS is used as a theft deterant system for gm cars. It controlled a relay for a starter solinoid, and it sent a signal to the ECM to get it to send a signal to the fuel pump relay.

The quick way to bypass it is to measure the resistance of you key. The 'chip' is actually a resistor pellet. If you have a Digital Multi-Meter (DMM), you can use the DC Ohms part to measure the resistance, and get that resistor(or equivilant combination of resistors) from radio shack, and use it. If you follow the wires down you steering coloum, you should see two white wires in an orange sleive connecting to a white and black wire, and a purple and yellow wire. Connect the resistor between the white/black wire and the purple/yellow wire. Assuming you have the correct resistor value plugged in, passkey(or aka vats) will enable the starter and fuel, and cosiquently it most likely means your lock cylinder is bad. If you permanently solder this resistor in or something, you will bypass vats completly. Meaning if you want to get a new key, you just have to have the cylinder's mechanical cut made up on a blank and it will work.

If you car still don't start, the realy or solinoid on the starter could be bad. Most likely the solinoid.

Joker

NEEDAZ

Just a heads up, on my 89 the VATS wires where yellow in a black sleeve. The chip resistors used in the keys are usually an odd value. If you have a mom and pop type repair shop around they should be able to check the keys resistance and supply the correct resistor... Good luck...

1bad91Z

iTrader: (1)

I've had the same problem for a while now and have solved it. A new battery went in, then a new starter, then a new ignition switch. (It was the ignition switch) because starter was new, fuel pump kicked on but the starter wouldnt even click. Besides if it was your VATS, the security light would flash. The car starts everytime now! Oh, by the way www.fastchip.com will burn you a custom chip and they will program the prom to keep VATS permanently disabled as long as the chip is installed. Hope this helps.

Tim Burgess

The signal that the ECM receives from the VATS module causes it to enable the fuel injectors, not the fuel pump relay.

You may use the "security" light on the dash to determine if the VATS system is disabling the starter. Normally, when the ignition is turned on, the security light turns on for about 2 seconds & then turns off. If the VATS module detects the incorrect resistance from the resistor in the key, the security light will turn on and stay on. If there is a short or open circuit in the two wires between the VATS module and the lock cylinder, the security light will not turn on at all when the ignition is first turned on.