1992 Mazda 323. 200,000 kms
Often idles very rough at stops to the point that italmost stalls. Changed plugs and wires two weeks ago. Did a diagnostic that said Coolant Temp Sensor. Replaced it as it actually broke off when inspecting it. Car ran great for about 10days. Now engine light comes on again...often right when engine gets to full temperature. Diagnostic again says Temp sensor but how could that be? Car will often come close to stalling at a stop.
When clutch is pushed in and in gear it idles ok but if you put it in neutral and take foot off clutch the idle drops right off. Can hear the revs going higher and lower. Any ideas. Is there an easy way to check for a vacuum leak at home? Is the intake manifold easy to inspect and put back together? Can the air intake sensor be cleaned with an electrical spray? Thanks in advance.
Don't want to be the guy stalled in the tunnel during rush hour!! Not good!!

 

i'm not sure about your 92 626. but i have a 98 626 and i experienced erratic idling as well. you could try changing out your spark plugs first. thats the cheapest thing to do. if that doesn't help, then change out your spark plug wires. if that doesnt help, for me, i had my fuel injectors cleaned out - took it to the local kwik lube and they flushed them out for like $60 - this took care of the problem.

i would ask a mechanic or do a search in this form on the intake manifold.