The hot start assist is simply a throttle opener activated when the engine is warm and makes it so you don't need to feather the throttle when starting it when its warm/hot/warmed up. The choke usually requires a couple pumps of the gas to start as ANY carb'd engine really.

 

isnt there another thing that helps a cold engine in the intake tunnel or whatever you would call it under the hood leading to the air filter? its like a little valve, and that bastard stuck on me one time.

--eric

 

your talking about that white hose going from the exhaust manifold heat shield to the air box, its supposed to warm the car up faster or something, its another one of the many useless things mazda felt it was nessesary to put on our cars.

 

Actually they are for cool days to prevent icying. Also, the Nikki fixed jetting of the carb is set for a certain temp range and will go lean when too cool(making cold intakes a bad idea without a air diverter on a stock air cleaner), and on really warm days it would bee too rich(when a cool intake may be a good idea at least when your not going fast). Anyway, cool days cause this "icying" condition when at part throttle for long periods with no hot air-diverter and will cause poor milage and weird engine operation since the icying acumlulates in the severe cases. The rememdy is to vary throttle often in that weather. Sidedraft carb intake kits have this condition too, most often occurs when its cool AND damp out. Dry+cool is NOT the same like a cold humid since the water vapor acts like a A/C system in the intake tract.

 

lol, i've seen my dellorto ice the intake when it was 90 plus degrees outside and it's pretty dry in colorado.

 

Yeah, the sidedrafts normally have some condisation going on after the butterflys. If its icying up, you'll see some frost forming around the upper part of the intake near the throttle plates. Ofcourse, the only way to see this is popping the hood IMEDIATELY after driving otherwise the exhaust will warm the intake up quickly and you'll never see it. I noticed icying much more in any weather when I re-jet and use E-85(ethanol 85% 15%gas) since ethanol acts much more like a refigerant then gasoline.

The best fix is to vary the throttle often IF your having problems. Or make sure your hot air divertor in a stock carb setup is working.