So this is my first accord that I've owned I'm normally into my Integra's. Anyway, so I purchased this 98 Honda Accord with a ULEV F23A4. The cylinder block is no good so I swapped the engine for a F23A JDM version. I swapped over any sensor and fuel rail because the JDM one was busted. So the car starts no problem. The only issue I'm having is that the check engine light is on with these codes P1166, P1167, P1399. Now P1166 and P1167 are both the primary oxygen sensor which I swapped out for new ones and still the codes are there. The P1399 I'm not worried about because I still haven't done the tune up and I know that's what it is, so once the car is warmed up the idle fluctuates like the TPS is bad. Now when I put it into gear the idle is fine. I've checked the antifreeze to see if it was low which it wasn't, also if I give it gas to fast the idle drops below 1k like it wants to turn off I'm lost and I need assistance please someone with more knowledge in this field can help me.

 

Have you checked the fuses? Three drive at least one of the codes, one under hood, one under dash drivers side and another under dash pass side?

 

stuck or dirty idle air control valve?

 

are you trying to use ulev ecu tuned to ulev f22 to run your f23? if so, this is the first problem you need to correct.

 

Yeah kinda figured that just can't find a f23a ecu

 

The ECU from your car should work with the swap. They are both F23.

In regards to the P1166 and P1167 codes, did you use an air/fuel ratio sensor instead of just a regular oxygen sensor?

 

See this other thread where the same ECU was used for the swap.

JDM f23 swap w/tranny questions - 6th Gen Accord DIY and Performance Forums

 

Finally someone with some knowledge thanks so much. I changed only exhaust manifold I'm going to try intake mani next on my day off whenever that is and I'll keep you posted.