89 tracker with surging engine HELP

i have an 89 tracker with stock motor. every time i turn on the park lights the engine surges from about 800 to 2000 rpm. does anyone have an idea why this is? so I need a new altenator?
thanks for any help

Sir.

pop the hood, now just up from the air-filter and to the right you will see a big metal thing with a nut on the left side of it, turn the nut so its loose then pull that metal thing back a bit or up a bit well you have your parking brake on and lights on... when you hear the moter run norm turn the nut so the metal thing wont move and that should fix it.


Sorry for the info there I have no idea what that thing is called but I have a buddy that had the same problem and thats how he fixed it... every now and again he has to do the same thing over again but it works every time.... also it works for aircare if you have it were you are.




cheers

check your ISC solenoid

My 89 Tracker surged for 3 years, only on start up until reached operating temperature. What corrected it was adjusting (turning clock wise) the Throttle Position Sensor... which is located on the throttle body. Loosen the two screw just enough to turn the sensor clock wise. Then retighten. Start up check the performance. Move it aprox 3mm at a time. This worked great for me .. Absolutely no more surging.