Cold Idle Good :o) ; Warm Idle Bad :o(
 

Why does it do this? When the car get warm(about half way in the gauge) the car idles really bad...... When car is cool, idles awesome drives great. When clutch is warm reverse slips, and vice versa. Is this normal(refering to idle not clutch)?

nah thats not normal: check out the FSM
Go to fuel and emissions control systems for n/a or turbo, whichever one you have, then go to page 14

http://www.cochran-racing.com/FSM/index.html

whoa, for starters, you need to post what model you have. If yours is N/A, then halfway up the gauge is a BAD thing. Even TII's don't usually get that hot, especially during normal driving. As far as the relation between temp and idle quality, I've only had scenarios where the opposite is true. Mine idles at ~1300 when cool with some missing, and when warmed up it idles at a consistant and smooth 750.

I would associate most common idle problems with the TPS, but if your car is really running that warm, then you need to check out whatever is causing it (Cold spots in radiator, bad fan clutch, "Oops there's no coolant in there," etc.) I would think running too hot might affect the idle, but I don't know for sure.

Edit: One more note... how's your oil level and pressure? My Supra was idling rough with low OP a couple days ago after I ran it hard, so I shut it off and checked the oil. It had burned off 1 quart in less than one hour! Filled it back up and it ran fine.

Its an S4 N/A and yea it does run really warm, i do have coolant and the fan does work, there are no leaks..... except for having to change the oil every fluid is wheres its suppose to be at

What oil are you running? I would suggest an oil change if it needs it.

I dunno what type of Oil its on now, i just got the car like 4 months ago, the car has been getting fixed and such over the passed 4-5 months in my backyard so it hasnt been driven much since i got it (approx 17.5 miles) I just bought some royal purple today and once i get my insurance info this week im going to chage the oil (10W30)

I'd stay away from Royal Purple, its synthetic. (Unless of course, you arn't running a MOP)

Do a search on synthetic oil and you will find TONS of information.

Ohhh no, I'm not going to touch the whole synth vs. dino battle. I am however about to switch to RP 20W50 synthetic in mine though :)

17.5 miles in 4 months!? Poor car, give it some exercise! Really, the rotaries I've bought didn't run that great at first because they had done a lot of sitting at a dealership or in a garage. Once I got them out on the street and ran them hard for a week or two, they ran great. Also, since you just bought it, make sure you change the plugs and oil, flush the radiator, and you might want to put some new gas in it if it's had the same gas sitting in it for 4 months.

Check your TPS at a warm/hot idle at the ECU. You need one volt, and it will vary a bit between different drives/ temp ranges, so find a happy average. See the link for pin locations & how to get the voltage reading...

If you have any block-off plates on the car at the EGR, ACV, or BAC spots check those for leaks also after she warms up. Check the entire intake path as well as you can, too. Spray some contact cleaner, brake care, whatever, to locate any leaks...

https://www.rx7club.com/2nd-generation-specific-1986-1992-17/troubleshooting-your-car-ecu-340578/

If everything above looks good, start checking your temp sensor inputs at the ECU and compare to FSM specs (in the link).

Please do not post unless you have even read the FAQ for FC sticky thread at the top of this section.

Your information is incorrect. You should have searched before you re-posted old wives tails.

Well i really can't run the car to much(no insurance/tag yet) When i do get insurance and all comming up this week when the tag comes in the mail, i should be able to change the oil at my dads shop. untill then im just look for possiblitys on why the car runs like that. the car has been sitting for 4 year prior to any of this so i do why running the car would fix alot of problems....thnx for the advice btw