'98 Prizm, 5spd, 100K. Pretty bad stumble whenever I try to accelerate, regardless of initial speed. Idles fine, Runs fine at speed, throws no codes. Replaced spark plugs, PCV valve, no change. Connected to OBD computer and data, like MAP, spark advance -- changes as you would expect under acceleration. I have put some injector cleaner in the gas now but that is a stab in the dark. This is my daughters car so I only have a few days to figure this out so I would appreciate some suggestions to pursue. I can't find an EGR valve on this vehicle, otherwise I would look there.
Seems to me that when the vacuum drops, the problems begin, then recovers as load is reduced.
Thank you in advance....
Travis