In my 91 dx auto hatch stock dpfi, if i floor it 0-60 lets say, there are flat spots when pulling through the rpm range under a load. at like 3500 to 3700 it will flatten out but then at 3800 it pulls noticeably harder, then does it again from like 5000-5200 then pulls up to redline like a champ. I don't do this routinely but there is something amiss I'd like to track down. I will make this car run perfectly if it kills me.

 

Check your timing belt timing.
Distributor timing.
Grounds.
CeL on? fix it.
Sounds like your timing curve has a re-adjust lagg. Normally this happens when timing is wrong. Common symptom is a stumble on start up then a smooth out. Timing correction is being made " out of the norm". At an idle the timing is retarded and under accel it advances.
Check your valve gap
Dist
spark plugs and gap
cap and rotor

MAYBE a bad dist, more likely bad timing, intake leak or tps.

 

Timing belt is dead on. just replaced it and triple checked my self. problem occurred before the belt change. i have to look into how to check the dist. timing. went over my grounds, check. no check engine light but ill look at the ECM. valve lash is due for adjustment. tune up wasn't more than 15k ago. how do you test the distributor? def no intake leak. just put the motor back in and did the carb clean trick. Tps is prob original. i guess i have some work to do.