Long, long ago I replaced my 88 HF intake manifold, with a 90-91 Si intake manifold, and put in an Si ECU. Now I know the EGR plug on the harness is jut not used, BUT there is a sensor on the bottom right of the intake manifold that the 88 HF harness does not have. I have looked befor on the ner, done searches here on HT, but have never seen anyone else speek of this. It has been running fine for months no proble. The only thing that happens is everyonce and a while it will throw a code 1 (oxygen content), which i think is coming from my O2 sensor being covered in burnt oil.

I am asking this because I have a JDM D15b on the way and want to make sure I do this right (I just didnt car about my current motor)

Now I dont remember what year ECU it is, I will look at that tommorow. I think there may have been a difference between the 88/89 and 90/91 harnesses.

I will try and get a pic up of the sensor that is on the manifold.

Thanks a head of time

 

Anyone

 

Which right? Ill guess and say its the fast idle thermo valve. If I recall the 88 si had that piece on the firewall. If you have had no probs with the FITV disconnected then id say you are ok.

 

If your loking in the engin bay from the front of the car it is on the bottom right. If you are right, where on the firewall is this sensor?

 

i did an intake manifold swap on my civic and i have the same sensor just hanging not doing anything. My car also has some problems idling (sounds like it misfires). i also have a code flash occasionally but it seems to go away as randomly as it appears. looking at you signature i have the same setup as you but with 1/4 of the miles and stock intake with stock tranny and stock exhaust