my 1994 lexus gs300 is idling at 2-300 rpm. i just did valve cover gaskets and it ran perfectly before. got new plugs and wires runs better then before perfectly fine at anything above 1500rpm anyone have any idea what the cause might be?

 

It’s been a while since I worked on that engine but what did you have to remove to get to the valve covers. Vacuum leak?

 

had to pull the whole intake plenum off to get to the valve covers and i thought vacuum leak but my last gs had a vaccuum leak n it idled at 800 ran fine also i checked for it didnt find anything

 

You can try to disconnect the battery so that the system can relearn but I really think you have a vacuum leak. Spray some water around the connections and see if you can hear it

 

okay ill try that when im off work

 

didn't find any vacuum leaks was talking to someone and they said try and clean the iac and see if that fixes it

 

Kinda late to the game here, but I’ve always used carb cleaner to look for vacuum leaks. Spray it around parts you had removed, if the idle goes up you found the leak. Obviously avoid spraying into the intake filter as that will always idle the engine up.

 

same thing i used to use carb cleaner , you should try it