I have a 87 RX7 non-turbo that I purchased a few months ago. It had been sitting in a field for around 4 years. Well, I cleaned it all up, replaced the plugs and cleaned the fuel pump. Replaced the gas/oil. It runs fine but when you first start it up, it revs to around 3000 for about 20 sec's(normal?) and then drops to about 1500. Here is where the trouble starts. When it drops, it sounds like it is only hitting on two plugs, however, you can hit the gas and it smooths out, let off of the gas and it returns to the miss. This continues until it warms completely up. The other thing it does is it jumps from 1500 to 1200 and cycles back and forth until it is completely warmed up. Then it runs fine and idles at 700 with no idle cycle or misses. The car also did this before I replaced the plugs.

Joe

 

yes i have exactly the same problem. if someone can help out its appreciated. or a link/reference to info we can use.

 

Yes, your car is supposed to rev to 3000rpms when the car is cold. It will do this for 17 seconds, and then it is supposed to drop to 1500rpms. It will then slowly drop to 700rpms slowly as it warms up. The 1500-1200rpms jumping back and forth is not supposed to happen, but it does happen on a lot of our cars. It won't hurt anything. Check all the stuff on your throttle body(thermowax, dashpot, TPS, secondary throttle plates) to make sure they are working to spec. If you don't want the 3k startup, just start the car in neutral, instead of 1st.

 

yeah, my T2 does the 1000-1500 idleing before its warmed up as well. you should check the TPS to make sure the readings were in spec. i check mine and it was way off...awaiting a new TPS

 

were are the thermowax, dashpot at?

 

"just start the car in neutral, instead of 1st."

ahh i always start the car in neutral, and it still happens. i also have underground heated parking, so cold weather is not an issue either.

if i have only parked for lets say an hour or 2 it doesnt happen, but if its overnight i pretty much always get the 3k startup.