OK. so i built a H23 bottom with a h22 vtec head. This is all thats done to the engine. Balance eliminator shaft kit. egr block. valves, type R springs and retainers. exhaust and intake. ect...

Its a well built and runs strong. I at first ran it with a H23(p14) ecu. non vtech. ran good for awhile. Ordered a chip p28. so i can get vtech. never ran good on that ecu. bogged down and intake pop. Spuddered when throttled up at lower end of rpm then rev normal at higher rpm. bought a p14(h22 vtech) ecu. ran alil better. but same issues. I checked the harness and had to fix acouple wires.

replace fuel pump, fuel pressure reg. map senor. main rely. tried different injectors. spark plug and wire. distributor.

It now idles and revs good. alil hesitation when throttled up. has idle problem. I checked the timing marks on the cams and are good. and off flywheel which are good. almost seems like a vaccum leak of some sort thats not letting it idle.

Put it in gear and drive alil, it falls on its face. rev up and rpms drop and almost want to die.

Not sure what it can be now. kinda stumped. would love to hear some ideas and advice. thanks

 

tune it. Hook up a wideband. check out afr.

 

If everything mechanically checks out, I agree with CXSERVER start with checking air/fuel ratios. It would also be wise to have your car properly tuned to insure not only proper AFR, but as well ignition timing. Hit me up if you need a hook up on a AEM Wideband, I got a few.

 

ok thanks. Ill look into that and if I need the AEM. ill hit ya up. thanks again

 

you should get YOUR h22/23 set up tuned specifically. doubt the p28 base map is similar due to so many other differences. good luck!

 

the P28 should run your engine if it's tuned right. obviously the basemap is totally wrong, I'm guessing the guy you got the base from has never tuned a swap before. Either that or you didn't specify what injectors you're using.
Not much more we can say about this, it'll never run right without a proper tune.