I just got a 1993 Vigor GS auto a few weeks ago and everything was fine at first but after 600 miles or so it has started low missing "like" idle feeling while sitting at a light and when leaving it feels slugish, missing, rough running but around 2700 rpm's it runs great, 2650 and below = slugish, rough running. I have cleaned the EGR valve and it did seem to help a bit and now today the "check eng" light came on so I have cleaned out the intake with carb cleaner, this seems to have improved the idle level but it is still rough and still not running smooth at the lower RPM's (and the Eng light comes on), it has very short moments when you feel it smooth out but then it's gone...it seems like a fuel issue (not 100% on that)....I would think that would only get worse as your RPM's went up??!???!? The car starts fine in the morning but after just a few min it acts up....but runs great down the Hwy

Any helpful hints before I try to check for codes tomorrow?

 

First of all, have you checked out why the engine light is coming on? Some times, when the engine light comes on, your can will run in "safe" mode. You should first find out whey your engine light comes out first, then start from there to fix the problem instead of just guessing.

 

If it wasn't for the check engine light I would say maybe replace the cap and rotor.

 

wow! thanks for the very, very helpful troubleshooting guide....with such solid advice I am sure this will be easy.

My guessing at what could be the issue was due to the rough running at stop lights and at low RPM, at that time there was no "check engine" light on...thus troubleshooting the problem and correcting issues step by step seemed to be the best course of action...but really your expert advice is going to be so much more help!

 

Joe, did you ever determine the reason for the CEL? Sometimes, a bad alternator will give the driveability symptoms you described while throwing a code for a bad knock sensor.

 

perhaps a bad fuel filter....