Hi
This forum is most helpful thing for my Rx-7 love since i,m from Europe and here isn,t many specialist.

My car:

1986 N/A 25.000 miles after new engine bought on Mazda.
Europe model with less emission control .

I have made full tune up here are things that i replaced:

New filters (oil, fuel, air - sport)
Fuel system cleaning - Car is runing 2 hours on cleaning fluid by machine
New Ngk platinium spark plugs
New Ngk spark plug wires
New water sensor
New thermostat
New fuel pressure regulator
New oil
New cat back (Inox made by professiona)
TPS adjustment with bulbs (factory manual)

But still my car is runing to rich i get with mixed driving 9-12 MPG (checked filed up - empty tank -refuel -calculate miles- refuel -empty tank etc....)

Also if i go over 6.5-7k when car is not waremd up completyl (not cold -please i have a hart) and deacelarate there is smoke (greyish, blue) behind me but not all the time (once and than not more or less). Also my idle is a litle bit jumping but not for more than 30-50 rpm, Also when i deacelerate my exhaust gos pambambam and it back fires a lot. But the

I thing maybe ther is coil problem (coils like in 85 GLS-SE, not electronic) or IAT or maybe air fuel mixture is out of order, i do not know where to check or what to do any more.

Ok fuel regulator helped a lot