I got a lsvtec all stock internals and such. When i use a p28 chipped ecu I hit vtec and runs fine when the engine is COLD. but as soon as it heats up about in the middle of the heat gauge the engine starts to bog and rpms idle under 1k. Im throwing a o2 sensor #2 could that be the problem? The head is obd0 in a 96 ek hatch converted to a obd1. Does anybody know what the problem could be? Thanks

 

replace the o2 sensor,that could very well be your problem then report back if you have any more problems with it