My 95 sunfire has a problem with rough idle at start-up.After a few minutes it runs fine except for a quick power loss at cruise.When accelerating it is smmoth but as soon as you level off and maintain your speed with a light load on the gas it starts to jek.Kind of a quick cut out/ surge.My mechanic put in on a scope and found no problems.Emissions were excelent and vacuum was good.He suspected a fuel pump going out but didnt want to put a new one in till he was sure so he advised us to just drive it and hopefully it would progress till it was easier to diagnos.I unhooked the O2 sensor and it runs great like this.I spoke with my mechanic and he now thinks this rules out the fuel pump.I kind of thought this pointed to the o2 sensor but he explained that unhooking it put the computer into the limp home mode and modifies the way the computer works.He suggested it might be the crankshaft position sensor but also added that we might want to take it tothe gm dealer and have them hook it up to their computer.Having had several bad expieriences at our local dealer I was thinking about just replacing the crank position sensor.Does anyone have any experience with a problem like this?Any suggestions?
- posted
20 years ago