Hi. I am new to the forum and have searched for this problem, but haven't found an answer directly relating to the problem I am having. I apologize in advance if it was on the home page.

I recently traded for an '89 Toyota V6 5 spd 4x4 that supposedly has a '95 model engine in it. I can tell the motor has been changed, but I can't verify the year.

I have an idle surge when the truck is warm and the lights are on, or if the brakes are applied. It also seems to idle too high when it is warmed up. Here is what I have tried so far....

I first thought brake booster, so I plugged the vacuum hose from the intake to the brake booster. It still surged when the brakes were applied. I tried this before I realized that I have the same problem when the lights are on without hitting the brakes.

Secondly, I figured that since the truck has a steel flat bed and trailer lights in place of real rear lights, that it could be a ground problem drawing power from the fuel pump. I grounded the fuel pump and same problem...

I am stumped. Could anyone please offer some advice on this issue? I appreciate the help!

 

UPDATE: I adjusted the idle down and it has solved my problem!