OK..so here's how it goes. My friend called me up the other day to wire in his Ls/Vtec in his 91 civic DX hatch. I went over to find that someone had already tried to do the MPFI wirng, no biggie i do them all the time. So i get all the wiring done, wire up Vtec,Vtec pressure,and the Knock sensor.

Started the car, it starts perfect, but not when you give it gas. it idles up and down real fast...and is giving codes 20, and 4.

The car is running on a PR4 ecu the LS. I am almost sure the code 20 is because on the ls ecu pin b19 is P/S Oil Pressure Switch. But b19 on a PR3 its Knock Sensor. and finally b19 on the dx is Electrical Over Load. But my buddy called me up to tell me he barrowed a PR3 and its giving the same codes.

The plug i used for the knock sensor on the motor one with two wires(EACV type plug), but the knock sensor only uses one, I think I need to switch the wire to the other.

Iam kinda stuck with it, but iam looking for a few opinons , My only guess on code 4 is that the Dist is bad.(CPK sensor)

Anyone have any ideas?