what is a hac sensor and what does it do?

[chefma70]

what does it do cause i dont have one.

i did a 7mgte swap i have a pre 89 body .i dont have a hac sensor will anything bad happen if i drive without one???

 

[shaeff]

Considering you're pretty much at sea level, you won't likely notice any difference. It's HAC- High Altitude Compensation. If you lived up in the mountains somewhere, it would be more important. Either way, just find someone who's parting out a car and ask for it. Should cost you about $10-$15 total.