So, its a 2005 rx8 my car wants to stall ( or so it feels like) when I'm stopped and the heat is on low or high. It's a manual transmission, the rpms drop to about 800 or lower...doesn't seem to happen with the AC. Heat comes out OK, but nothing wonderful. I always let the car warm up, I have read to much about people flooding their rx8s in the winter. I haven't tried doing the temp. check 0-16 on my dash yet? If you guys have any clue what it could be, it would be greatly appreciated. Thanks-

 

800 rpm is actually normal speed at idle (actually 750). Does the car actually stall? how many miles are on the engine? When was your last maintenance check? Give us as much detail so we can help as best we can

 

Hmm... I would want to say that it probably has to do with the cooling fan cutting on and off, and taking a little bit of the power which is making the rpms drop a little bit. But if it doesn't happen when the AC is set to cold also then that wouldn't make perfect sense. Next chance you get, have a friend stand by the hood while you sit in the car, and see if the rpms drop at the same time that he hears the cooling fan turn on, then if they come back up when he hears it cut off.

 

The car has 65k just got a new clutch put in Idk if they checked anything under the hood, maintenance wise. And the car doesn't stall, I push the clutch in and just go a little higher rpm when going into first or reverse from a stop. That's when I'm having problems when I come to a stop sign or just stop...really annoying. I heard it could be a IAC that comes off the throttle body? Should be cleaned after 60k ? I'm not sure how to take it apart yet..wanted to get some opinions before I make a move. - I will try the cooling fan tomarrow. Idk what it is. All I know is its winter with 25 degree days. Ah sucks.

 

read this thread and see if you experience the same issues: https://www.rx8club.com/series-i-tech-garage-22/stalling-idle-problems-quickie-tb-iac-test-172129/
Rough idle is caused by a lot of things. Bad plugs/ coils, dirty MAF sensor, etc etc.

 

Ya I think its IAC. I need to clean it or get it cleaned, I could get the plugs replaced. It all comes down to money with these cars haha. I will try these different tests tonight after work. I will let ya know what I see I might just have a mechanic clean it ( IAC) so many possibilitys

 

You also might want to take a peek at this thread - https://www.rx8club.com/series-i-do-yourself-forum-73/diy-test-neutral-reverse-switch-200453/.