C S

So finally got my RX7 running that has under 20k miles and has been sitting for a while prior to my ownership. Replaced spark plugs , Pumped out all the old gas , replaced fuel filter , filled it with 5 gallons 93 octane, no start. Replaced the fuel pump with a new unit and it starts no issue - but cold start it idles 2-3k for a little and drops to 15-2000. The other day it Idled warm at 750 , but today it was high, also it sounds a little funny? I’m new to rotary’s . I replaced all the spark plugs before I did any other work, and I know they’re correctly in but it almost sounds like it’s misfiring? Keep in mind the OEM mufflers / Y pipe on it now is shot has holes and is no good. Take a look at the video any opinions or advice appreciated

C S

C S

Also anyone have an idea what this is? Idle

related ?

cgunnr

oooh, haven’t watched the video yet but that’s the silly s4 idle mixture pot. It’s literally just a potentiometer but yours seems pretty messed up. See if there’s any way to turn the screw; L = less fuel (lower idle) R = more (higher idle). If not just don’t bother tbh you’re not really supposed to touch it but mine was shot so I just replaced it with a generic Amazon potentiometer and it’s ugly but works 😂

cgunnr

that said, your idle honestly seems pretty normal. The 2-3k is part of the FC’s AWS, or accelerated warm up system. it’s a factory feature that idles the car high till it warms up and it’s controlled by the thermowax, which is a cam on the throttle body that moves with temp. I honestly don’t hear a misfire but I did notice how it dropped and tried to catch itself a couple times. could be worth cleaning your IAC valve or adjusting your idle set screw just to see how it responds. usually you never have to touch the mixture potentiometer in your other pic, but if you can get it to turn maybe mess with that a little. Could also be a TPS calibration issue. The TPS is known to cause a whole host of weird and wacky issues on these cars. All the old potentiometers just kinda get weird over time. There’s a TPS adjustment procedure for the T2 on FC3Spro.com . best of luck, and let me know what you find! <3

C S

Thanks I'll get at it tomorrow! Will let you know how it goes. Thinking maybe if I keep letting it run and short drives on my road maybe the old gas that was sitting for years will burn out and it'll idle like new

cgunnr

yeah honestly it’s super possible, rotaries can be a little picky with old fuel in my experience. driving and getting that engine lubed up is probably good since she’s been sitting so long too. idle quality is idle quality and it won’t blow up your engine or anything lol. just tune as necessary and you’ll get it dialed. He’ll, my idle isn’t even perfect, it changes between stoplights sometimes and changes with air temp, and I’ve been daily driving my fc for a year. these cars are just old and a little quirky sometimes. get that exhaust leak fixed and you won’t even notice it