hey guys need some help here!!!! Alright i have an EG and swapped a d16z6 and after about 6 months the car would idle real low on a cold start, but after it warms up the car runs like a champ and idles normal. The car cuts off at 5500 rpm. I have no check engine lights and i checked all my grounds and every thing seems to be fine. I thought it was the ecu so i swithced my P28 for my friends and it did not make a differance.
Last week i swapped the motor out and dropped in a jdm b20 and its doing the same thing as the sohc motor i had. I am also using a p75 ecu instead of the p28. No check engine lights

 

Check VTEC engagement point.

 

check your timing belt or fuel filter...