I have a 1987 2.5 with FI and a manual gearbox. When I drive the RPMs stay high, even when I come to a stop. Blipping the accelerator drops the RPMs down to normal. No vac leaks that I can find. Everything stock
Why do they stay up and come down when I rev up the engine? What should I check for first?
Thanks!

 

I'm thinking this it a throttle position sensor issue but have you checked for leaks around the intake?

 

I don't think leaks would react to blipping the accelerator. The RPMs stay high until I goose it with the clutch in, then they drop off to normal and stay there until I start to give it a little more gas again. I can let it sit along time without touching the accelerator and the RPMs stay at normal. It almost feels like a carb would if the butterfly was sticking open.