bouncing idle
 

My idle just started to go haywire yesterday. Idles at 900 than down to like 200 than back up to 900 totaly spuratic. Also when i am accelratoring it has hesatation. could some one please help?

Anti-afterburn hose maybe.

http://www.mazdatrix.com/c-5.htm

Maybe even the shutter valve.

I have been experiencing the same difficulties with my GSL-SE. It doesn't happen very often, but when it does, is mostly on hot days. This started happening a couple days after I adjusted the idle.

Thanks ill check that hose. Thought it might be a cloged cat? maybe bad ing. wire. Am i on the right track? anyone...anyone Like i said supratic

could it be a bad coil?????

some one please help just checked out what i think is the anti-afterburn hose seems good (didn't take it off..felt the whole length of it no cracks that i could see). Dont hear any noise (hoonking)so im asuming it is not the shutter valve. Please help?

Can you describe the symptoms in a little more detail? I assume you have a 12a engine, yes?

yes 12a nikki carb... when i am sitting at idle the engin will sit at 900rpm
for any where from 10 sec. to a minute and a half just loke it allways has than it drops like it is gonna stall. On the tach. it bounces between 0 and 300 rpm like it is not getting any fuel or starving for air than like a switch it levels of at 900. And when i am driving it hesatates on acceleration(once agan this is spuratic. I hope i havr given you enough info for my sake. Sory about my terreble gramor and spelling and once again thanks for all the help

hmmm, your idling problem kinda sounds like the shutter valve to me. Mine would idle high with a large sucking/vacuum sound in the air box then it would suddenly drop and idle like crap. It was my shutter valve. I disabled it by plugged up the large hose going from the airbox to the shutter valve and it cured my idle instability problems. After do that I re-adjusted the idle and mixture screws and she's been idling great ever since. Do a search on this forum for shutter valve, it just might be your problem. Good luck!

--Bob

hmmm, your idling problem kinda sounds like the shutter valve to me. Mine would idle high with a large sucking/vacuum sound in the air box then it would suddenly drop and idle like crap. It was my shutter valve. I disabled it by plugged up the large hose going from the airbox to the shutter valve and it cured my idle instability problems. After do that I re-adjusted the idle and mixture screws and she's been idling great ever since. Do a search on this forum for shutter valve, it just might be your problem. Good luck!

--Bob

I'm with Bob on this one. My '82's shutter valve went bad, and my idle did the same thing as yours. You don't typically hear the honking noise that signals a bad shutter valve when the air cleaner is on and the hood is closed.

like i said no honking noise ever?? could it be something else and why am i suffering from spuratic ?? or could that be the shuttervalve also

my car did the same sort of thing under high electrical load, like headlights and brakes, turns out it was a bad alternator.

not happing under load and never idle over 1500 but i will do the shutter valve thing in te morning. could anyone tell me exactly where its at.
By the way thank's everyone.

All I can suggest at this point is to check the basics: fuel filter, air filter, cap & rotor, wires, plugs, check for vacuum leaks, etc. and go from there. A bouncing tach could also be an indication of something bad with the trailing ignition. Good luck!

WHERE IS THE SHUTTER VALVE HOSES?????

Dude, do a search through the forum for "Shutter Valve"

But if you must know, it's the big fat hose coming out of the bottom of the air cleaner on the Driver's Side.