Last night on my way home, I reved my car past 6,000 rpm. Well, now when it's sitting and idling in the driveway, it idles at 1,500 rpm and sounds like it has a miss in the engine. When I'm driving down the road, it sounds and drives fine, but when I let off the gas, it surges. Can anybody help me out here? I don't want my rotary rocket to die

 

You have a vacuum/air leak somewhere. Check all of the hoses big and small. You can spray starter fluid around them to find the leak. Your car will idle faster when you spray around the bad hose.
hanman

 

Very good diagnosis, AZ85RX7. That sounds just like a vaccum leak.

 

I had the same problem...it bounces around when idleing. mine finally went alway . Did you do anything like put a fuel injector cleaner in the tank or anything like that??You may have bad gas or clogged fuel filter. make sure you are using "regular gas"..when was the last time you replaced the fuel filter?..you may want to look at that as I replaced mine. lubricate the linkages also. hanman also had good ideas. Lastly, it could be an adjustment with the TPS screw ( I think they call it)...You just have to experiment a bit. Mine went away after I did these things....Good luck.....cjf

 

I changed the fuel filter about a month ago. I got the gas at the same station I always go to, and I haven't added anything to the gas. So it can't be that. I'm just curious as to why it started last night when I revved it past 6,000.

Also, is it a bad idea to drive around with it like this?

 

hello? anyone????

 

It may just be a sticking linkage. Especially if you do not rev it that high very often, when you opened the throttle part of the linkage got stuck in the dirty area. I would try cleaning and oiling the linkage around the throttle body (or carb if it's a 12A).
Idling around 1500 won't hurt the engine.

-John.

 

Thanks FJ, I'll try that.

 

**** my 80 done that all the time, especially in wet weather. Or in extreme temperature changes. Sounds like whet they refer to as Vapor Lock. What I did was while it was running, put my hand over the carb opening covering it completely, and rev the motor up, then pull my hand off. It would try to flood out and die, but if you hed the throttle down it would straighten up for a few more days...

 

Seems like everyone has a different opinion on this. Considering it didn't happen until after you reved past 6k sounds like your secondaries might not of closed all the way. Just a little open will increase the rpms. Little cleaning and lubing may help

 

Try checking the vacuum lines and or the air pump. The air pump could be malfunctioning because it is supposed to keep the RPMs up when you go to shift. Also check the regular fuel line items: fuel filter and carb, if applicable.