idle problem

[1of1035]

If I drive somewhere close by then shut off the car and let it sit for just a few minutes(like running into a store) when I start it back up again it will idle at 2500-2700 for about 30 seconds then it drops back down to normal idle. When the car sits overnight or for a long period of time and I start it up everything is fine. It just started doing this a week or two ago. No codes on scanmaster besides a o2 code(45). IAC and TPS are set right and I have no vacuum leaks. Anyone have any ideas?

 

[87ttypeV8]

my idle was off the wall before because of a bad 02
i kept getting the code for lean condition i think, cant recall the # but i simply bought a new 02 and all was good

mine wasnt as bad as your idle though... mine would bounce from like 1400-800 and everywhere in between!

hope ya find the flaw!

 

[1of1035]

thanks. Its only when the car runs then I shut it off for a few minutes. Otherwise its running great. I just picked up a denso o2 so i'll see if that fixes it.