I have a first Gen b16a that I have swapped into a 90 civic hatchback. It ran great for a little over a year, then started to notice that the tach was jumping but rpm actually was staying the same. Then the iac code came on. So I replaced with new, but the code never stopped. Then started to not be able to get on it at all, I could put very light pressure on the gas and get up to 3 grand and then it will bog out. If I put too much pressure it completely looses power but once I ease off of it picks back up and slowly starts to climb again. But never past 3k in any gear. Replaced the distributor with brand new, but swapped to 0bd1 along with pr3 ecu and o2 sensors. Nothing changed. New tps sensor, water temp sensor. Iac code is still coming up with new ecu and now crank position sensor code is throwing too but my engine doesn't have one. Please help. I am at a loss

 

sounds like you are in limp mode. chances are it may not be the actual iac valve that has gone bad. i had this same thing happen in my bone stock 98 civic ex w/ y8 motor. i replaced the iac, same issue. finally took it to a shop and ran a better scan tool. with their help we were able to diagnose that it infact was not the iac tripping the code. first we saw temp reading were off. so we swapped the coolant temp sensor, fixed sligtly. then also swapped out the fan switch. and bam problem gone. no more cel.

 

I swapped a first Gen b16a into my 90 hatch. Got it running really good. Ran great for around a year and a half then noticed that the tachometer started to jump around at high rpm. Usually 6k-8 but the engine rpm was actually staying the same. The it got worse and was doing it at lower rpm but the rpm was now jumping around as well now. Then it got really bad and it wouldn't even go over 3k like it was going into limp mode. When you start the car up it would be fine drive it for a little and then it would backfire and go into limp mode. So I ordered a new dizzy, but I ordered an obd1 and the jumper harnesses for it and ordered a p28 obd1 ecu and the jumper harnesses for the that as well. Put them both on with a baseman tune for my engine and the problem still continued. Then it got even worse. If I lightly pushed on the gas it will slowly climb in speed but only to 3k in each gear. If I pushed too hard it will loose all power until I released the gas. I started replacing everything I could think of. Iac valve, tps sensor, water temp sensor, fuel injectors and pump, o2 sensor. I'm at a complete loss and don't know what else to try. The only cell being shown is the crank position sensor. But my engine doesn't have one. Please any advice would be great

 

Post the CEL codes.

https://honda-tech.com/honda-civic-d...lists-1901557/

 

4 and 14

 

If you reset the ECU, do both codes return?

 

Yes

 

Measure the resistance of the CKP sensor from the two CKP sensor pins in the ECU connector. Post the Ohm reading.

 

That's the thing tho. I don't have crank sensor on the block. So I don't know where it would be

 

The CKP sensor is located inside the distributor. You're are mixing up the CKF and CKP sensors.