I recently had the transmission replaced in my 1992 Dodge RAM 250 Diesel. At the same time the Throttle Position Sensor was replaced as well The idle is now much higher than it was before, so much so that the engine shudders when I turn it off. My mechanic tells me that this is normal, but it never idled this fast before I changed the TPS. I'd like to reduce the idle RPM. Can I do this myself, or do I need a mechanic to do it?

Thanks

 

There should be a data plate on the valve cover of your engine. On that cover should be a spec for idle speed. How does that number compare with the RPM's that you are currently turning at idle?