Weird Idle problem

[Justin8763]

Hey guys this is my first time posting on this forum, and I've been looking around to see if I could find an answer. I'm thinking its my PCV valve, but I wanted some input from you guys.

When I start my car, it idles around 1500-1750 RPMs. Strange thing is, when in park and after i turn on my car, if i hit the gas a bit, it revs up and stays for a good 30 seconds to 1 minute, and then starts to SLOWLY fall back down to 1500. When I start driving for a while, it goes to the normal 800 rpm idle when in drive. Any Ideas?

My car is an 88 Lx-i

[A20A1]

Is your coolant level full?

[Justin8763]

Yep. My old radiator had a hair line crack in it, so I had to replace it. I flushed out the system and refilled.

[shepherd79]

check the throttle cable, make sure it is not tight. Also on the throttle body, there is a diaphram that allows idle to slow down slowly when you let go of the gas after hard driving or shifting.