Just did the dpfi to mpfi and obd1 conversion on my 88 dx running a chipped p28 with custom base map, runs great but pops at idle and jumps around at between 800-1100 rpm sounds like a slight miss fire and sometimes will jump up to 1500 and stay there for a while. Tried new spark plugs and o2 sensor and unplugged a few sensors but didn't seem to effect anything car runs a bit rich not sure if that's the issue

 

No codes?

 

No

 

Try running a obd0 si ecu or virgin p28.

 

It did it before I chipped the ecu and on a p05 ecu Pm6 wouldn't work cause I would have to wire in a resistor box and a different o2 and dizzy

 

Anyone??

 

Did you invert the tps wires?

 

Yes I doubled and tripled checked all my wiring