RPMs dropping

Just wondering if anyone had any ideas…

When my '99 ZX2 (5 speed) is warmed up to normal, I press the brake pedal, and the volts go from 14 down to 11. This is accompanied with my RPM dropping to around 500. I’m thinking vacuum leak, but can’t seem to find anything. If anyone has any ideas at all, I’d be very happy. P.S. New alternator, serpentine belt, battery, pcv valve, and the intake manifold was just replaced.

Only happens when you press the brake pedal? Do your brake lights work correctly? Sounds like maybe a short to ground in the brake circuit. Check for cut/bare wires at the BOO(brake on/off switch) located near top of brake lever towards firewall. Also check to see if their’s water in you tail light housing causing a short. Hope this helps.

Thanks for the idea. Lights work fine, but the idea of a short somewhere is a good one. I started chasing wires tonight, and my search will continue. Should have thought of that myself, since I do work on aircraft, :oops:, but thanks for the idea.

Well, I found a short in the brake light wiring, and also a leak in one of the joints in my intake tubing. All fixed, and working great, now. Thanks for the help! Appreciated.


Ride On! :lol: