About 4 weeks ago I did an engine swap. I now have a h23a3 engine with an h22a dohc vtec head. I didn't have the vtec connected or computer so i just drove it normal and everything was running fine. Until last week i finally got the computer and connected my vtec, but now every morning when i start it, it starts like bogging or stuttering when i leave it in neutral and hit the gas. I let it sit for a while and it goes back to normal. Then i drive it and after about 15 minutes of driving it starts bogging again in every gear. In every gear it does it until i hit about 3000 rpms and then it drives normal. I disconnected my vtec to see if that was the problem and it still does it. any ideas on what it could be?

 

I don't understand why more and more people are doing swaps with no research whatsoever and then wondering why their car is running like ****.

There isn't enough information given yet to make any determination as to what the issues are.

 

couldnt hurt to test tps and check crank/cam alignment.
could be a craptastic ignition component too.

https://honda-tech.com/honda-crx-ef-...hread-2830131/

Advanced Ignition Troubleshooting - Team Integra Forums - Team Integra

 

I had the same problem on my 5th gen and it turned out to be the cap and rotor. Give that a look. If not that, check the TPS voltage.