EmboRotary

Hi all,

Bought my '85 RX7 a couple months ago and it has always had an erratic idle. I thought it might just be a rotary thing, having never owned one before. The thermostat was stuck open, so it never got up to choke release temp until recently when I replaced it. Now it feels like it's misfiring at idle all the time, with the choke pulled in or out, but it definitely gets worse once the choke has released completely. Sometimes when putting it in neutral from coasting, the tach indicated the revs dropping to about 500 ish then going back up to around 750 and infrequently the revs will drop so much in neutral that the engine will stall itself. Keep in mind, once you're on the throttle, the misfire clears up and it revs perfectly all the way to 8000.

Some context, the previous owner has deleted most of the rats nest, looks like there's still 2 solenoids there, even though the car doesn't have AC. It also seems like it wasn't done too professionally, so I'm wondering if maybe there's a vacuum leak somewhere. Also, very infrequently, the car will make a honking/wheezing sound when crawling while slipping the clutch. All the times this has happened, the windows have been up so I can't tell if it's a suspension or induction noise.

Anyway, does anyone have suggestions for where to start diagnosing this? It still has the stock Nikki, so maybe a tuning issue or shutter valve?

Many thanks

EDIT: It also bucks around quite a bit in 3rd and 4th gear under 2k RPM on decel, maybe something else to point towards shutter valve?

diabolical1

iTrader: (3)

vacuum leak is definitely a possibility. i would start there. next on my list would be making sure the idle mixture is set correctly.