Volvo: 1991 Volvo SE, throttle position sensor, volvo

Question
My check engine light came on with code 2-3-4 (something about throttle).  Can you tell me what and where to check.

Thanks

Answer
Pat,
That indicates the throttle position sensor on the side of the throttle housing. Make sure that just as the throttle comes off idle you can hear it click. If not then you may try an adjustment and cleaning. Clean the housing with carb spray cleaner and adjust the throttle to one turn after it touches and opens the plate. The switch is adjustable also. It must click as soon as it opens.