99 astro AWD
completetuned up 2 months ago
2 weeks ago started to skip/ buck
added gas treatment and 2 tanks of gas still bucking
does not buck/skip under a load or acceleration
bucks/ skip not under load at any speed seams to be at a certian position on the gas pedal
could it be fuel injectors or a bad distributor?? Can someone help?[]

 

My '97 puzzled me for months with a similar problem. I had erratic skipping/missing, but it always went when the pedal was on the floor. It also idled fine. I never had any trouble codes and the MIL light never came on. Finally I tore out the distributor on the advice of a friend and the gear was horribly worn. Changed out the gear and it's been fine. A shop with a good scan tool can look at the cam retard timing and tell right away if this is an issue. Mine was floating somewhere around -30degrees. It should be +/- 2 degrees I think. Maybe this helps? I'm sure there's more than just one bad gear out there that was heat treated on a friday afternoon!