wrangler 1990 2.5i . i just replaced my lambda sensor, was quite a hassel since the one that got out had three cables and the new one four. colours where different too. eventualy i figured it out (i guess)
now gas mileage is way better but...
when i start it it runs terrible for 1 to 2 minutes in every gear or rpm. (fluctuations in rpm of around 750 to 1000) after about couple of minutes it runs just fine (idle 900 give or take).
when i turn her off and start her again. same routine.
she had a full service, injector cleaner, clean spark plug covers etc.
pravious owner drove probaply long time with busted o2 sensor. maybe the computer is out of wack? are there other sensors that could be busted?