Hi, my 92 rocky has recently started to have rough idle. It seems to happen more when the engine is cold, but the effect is that the idle oscillates between around 1k to 1.9k rpmÃ¢â‚¬â„¢s about once a second. Everything else seems fine, the vehicle drives fine, but just has this funky idle. I have casually checked the vacuum hoses and did not see anything wrong which was my first guess as to what could be causing this. Any ideas on where to look? I have read that the O2 sensor could cause this as well?