I have a 85 GSL it has 49,713 original miles but needs work on the motor. The problem is it runs great on choke but when the choke kicks off it runs bad. I dont know if its electric or if it has a pluged cat. It has new Factory Mazda starter NGK plugs and wire and K&N filter. I know the motor has good compression I checked it with the Factory rotory checker. It has 7.0 KG in the front and 7.1 KG in the rear. Both have even compression on each chamber. well thats the story can you help please !

 

Sounds like carb problems. First check ALL of your vacuum hoses. Look for air leaks everywhere. Use water in a spray bottle, starter fluid if you are daring and careful, propane in a hand held torch (unlit of course) until you find the leak. Check your float bowl sight glasses (front and back) make sure the fuel is 1/2 way up the window. If not, you need to set the float levels. I see that you have new wires, plugs and air filter. What about fuel filter and timing?
hanman

 

It probably is something in the carb. If it runs good with the choke on then I would suspect that your carb needs a cleaning.
Turn the car ignition on (don't start it) then look into the carb and turn the trottle by hand you should see a good squirt of gas come out if it doesnt then you have a plugged jet. If gas comes out before you turn the throttle then you have a bad float in the carb. Either way nothing to worry about.

Vic

 

When I first got my 7... Wow. Has it really been two years.

Anywho. It exhibited symptoms that you are describing. The DSPO (Dip **** Previous Owner) had increased the idle to hide it, but the thutter valve was bad.

See if air is sucking down this pipe.



It's sometimes accompanied by an air wooshing noise, or a honking noise. Mine sounded like a goose on crack being sucked into a shop vac in a tornado. (My wording on this changes every time I post it cause I can't remember what I called it last time.)

 

Forgot to tell you how to fix it.

Just pull the hose from the bottom of the blue air cleaner box and shove something down it. You don't really need the shutter valve.

What it does is cuts air and fuel from the rear rotor on deceleration to stop backfiring.

 

thanks to all of your help I now have the car running thank you you guys are the best your friend chris

 

thanks for your help

 

Not a problem, it's what we're here for.

C'mon back anytime.

 

That has got to be THE most helpful post EVER!
I just had to say something about it!

ALso, every first gen I have purchased has had a bad shutter valve.( I am quite good at replacing them now, so of course now I remove them and plug up the holes!)