Miata has rough idle and stalls out

[Tnemec5]

Question for the gearheads here, I was driving my Miata today, and everything was running fine, when it acted as if it was missing, but would still maintain highway speed, but at lower speeds like traffic stop/go it would just droop and stall out. I pulled over and it would barely idle, and then die again. I could give it throttle and keep it running, though it is running very rough. I limped home and I switched out the plugs wires and spark plugs. Still nothing, and if I don't keep giving it throttle it will die, but always restart, with a little difficulty.

Any ideas? What should I check, and in what order?

[Phatmiata]

Have you made any recent changes to the car? besides plugs and wires?

[kung fu jesus]

If your intake is stock, check the big, rubber crossover intake tube that runs from your MAF (the silver metal contraption on top of your airbox) to the throttle body. It is common for these to dry and crack as they age, letting unmetered air into the engine. You may have to remove this to inspect it. Flex it carefully and look for cracks. Most often they occurat the accordion-looking area in this tube. Also check for holes where spinning engine bits may have rubbed through it, like the alternator or waterpump pulley areas. If you find a leak, you can repair it with a few winds of black electrical tape stretched over it.

[lowandrusty]

Jump the ground and ten terminals on the diagnostic port and count the long and short blinks of the check engine light with the ignition on. My guess is that you may see code 34. That is the code for the idle speed control valve. They can stick or fail all together as these cars get older, its not uncommon. If that is you problem you may be able to remove it and clean it. I'm new to this site and haven't checked, but there is bound to be a thread on cleaning those!

[iKhanh]

did you ever get it figured out?

on a related note, my 90 with a stock 1.6 with like 125,xxx miles (aside from an ebay cone intake filter with adapter for the AFM) is idling kinda high, like between 1200-1500rpm. before it would idle normally aside from the HLA ticking. i noticed it when i was driving it a while ago: i was taking some turns i braked for, but i felt like the car was pushing me, accelerating through the turn. i figured the throttle stuck, so i put my foot beneath the gas pedal and pulled it back, and yeah, it did the trick. but it would still kinda stick every time unless i pull it back. i sprayed my throttle body butterfly plate to hopefully clean it of any gunk, but it would still stick. i disconnected the throttle cable, and it idled fine, below 1000rpm. but it has what i feel to be the appropriate slack in its tension. i haven't adjusted the idle speed adjustment screw either. spray some lube on the gas pedal and throttle cable springs, but still, no drop in idle.

i read about idle speed control valve from this http://www.miata.net/garage/isc.html. i was thinking about starting a new thread about it, but found this and wanted to post a response here first. has anyone had the same/similar symptoms? has the methods in the aforementioned link had any good results? because it doesn't seem like there's a real fix for it. any possible ways around it besides an engine swap? lol