2001 head swap on a 2002
 

I'm having a major problem with this. I just swapped the head and i didn't know that the 2001's are non-vtec. The problem that i'm having is that when i start the car it runs fine, but after about 3-4 minutes it starts to hit like a rev-limiter @ 4000 rpms. It runs fine besides that i really dont know what to do. I did this swap for my brother and it's just not going past 4000 rpms. I think it's the ecu because it looking for v-tec and not finding it and i guess that it's hitting like a safety or something that wont allow it to go past 4000 rpm, but as soon as i restart the car it goes away?? Any help would be greatly appreciated. Sorry if it sounds like i really dont know what i'm talking about i'm a mitsubishi guy, did the swap as a favor for my brother.

2001 civic EX's have v-tec engines, so you probably got the head from a LX, DX, or HX. My bet would be take that one back and get the other one. I am pretty sure that is why you are having this problem. My friend had the same problem, he had a 88 crx with a v-tec engine and he put a 95 non-v-tec engine in there, in it did the same thing.

Its the ecu you have to use the ecu from the car you got the head from and depending on what model it is yeah the ex and hx are vtec

yeah u will need the ecu... at 4000 rpms it is trying to change over to the different lobes on the cam...