I need to know if I have a ground or a BAC issue w/my
car. I have an A/F ratio guage and when the I turn the
headlights on the lights on the guage drop. Also when
I apply the brakes my dash lights dim. This is irritating
me because while driving at night it's hard to get a good reading from the guage, plus it would just be nice
to fix it.

I am keeping the BAC even though my A/C doesn't have
a belt on it yet, and I have grounded the guage in more
than one spot to try and solve this problem. Would this be a problem with the BAC or a grounding issue?

Any ideas would be appreciated.

mothership
'87 N/A w/mods

 

check your ground wires/connections? I have my o2 sensor directly grounded to the frame.

EDIT: A/C: bac ony compensates when it knows the AC is on. the ac has a clutch in it and doesn't produce much load when it is off.

 

What do you mean your O2 is grounded to the frame.
Mine only has one wire from it and I put it to the O2
wire from the back of the motor. From there I T'd it to
the A/F guage. Is that ok, or am I missing something?
So it's not the BAC for sure, correct? Thanks

mothership
'87 N/A

 

The bac is not making your o2 sensor do wierd things.

I specially grounded mine to the frame because it was not getting a good ground through the pre-cat. I would re-ground it just to make sure that you were getting a good connection.

 

nonameo......put a freq meter on the bac's wires someday any you'll see the duty cycle change as you turn the lights on or the heater fan , or step on the brakes.

Sounds like he said, bad grounding or bad output from the alternator to the battery. Maybe also a bum battery.

When he said ground the 02, he meant getting some wire and clamping it onto the body of the 02 sensor and then grounding that wire to the engine or chassis.