Ok so we did a h22a4 swap into my boys ek hatch- vtec is reallllly weak sometimes and sometimes its fine for about 3seconds and falls off, this is with a unmapped p28 ecu- now when we use a p72 (i have experienced in the past this works great on H motors) the car barely wants to run and is slower then stock. no MIL is present with either ECU car has great oil pressure, no dents in oil pan or anything, im really confused on this situation. If you drive the car with out going into vtec is feels smooth as can be,idles great,starts great (cold or hot)... were out of ideas ANY INFO YOUR SIGESTIONS WOULD BE GREAT

 

anyone?

 

no info?

 

slower at vtec with the p28 would be because the iab's aren't opening since that computer dosen't support that option. the p72 can control the iab's but the signal is differant than what the p13 would use. one throws a ground and the other a source of 5v's. i would suggest using the oem computer since the fuel and ignition tables are correct with either for the h22. you will notice a differance with the p13.

 

thanx, i guess well try one of them out, anyone know if this problem could also be related to the vtec solineid

 

in other words the iabs aren't opening up and while vtec might engage it won't feel like it is. they stay closed with a vacume box and a solenoid. try pulling the vac lind off the mani and plugging it up along with the vac line and run it once. if you feel vtec then it's due to the computer.

 

yea we already tried that ****... no different

 

all I know is the ECU is looking for 3 things before it gives VTEC the ok:

1.proper coolant temp
2.proper oil pressure
3.vehicle speed has to be over 20MPH or so

 

v-tec sucks were bout to put a h23 in ther lol