so i have a jdm b16 and my stock p28 ecu runs the car without throwing a check engine light what could be wrong?

 

so whats the problem?

 

i thought that if the p28 was not chipped then then it would throw a check engine light? i now for a fact that that ecu is not chipped.

 

hmmm. the p28 is a SOHC ECU, so it SHOULD be i believe as well. Did you drive the car with the p28 in? does it come on after driving? when you engage vtec? does the car/motor act unlike it should be?

 

you now i didnt actually drive the with the p28 in it i just started it up with it then put in a chipped p28.

 

so you have a chipped p28 AND a non-chipped p28? im willing to bet if you drive the car with the non-chipped p28 it will trigger CEL...especially when u hit vtec...

 

hey thanks for your help.

 

i don't think you would get a cel for it not being chipped but it may just be not putting the right mixture since for example the p28 is made for single cam and b16 is dual, i have a p28 with a b16 before and i got it chipped it didn't throw a cel either.

 

Tell us how "the mixture" would be different between a 1.6 SOHC Si motor and a 1.6 DOHC motor.

 

you should be able to run a stock p28 with jdm b16 motor without throwing a cel. what year is the motor? do you have a conversion harness? if its obd1 then should be fine. the only problem would be is that the ecu fuel/air ratio would be too low and make the car run weaker then it can handle. b16 has more aggressive fuel/air ratio than d16 since its dohc. put it this way...go test it out with the stock p28 and compare it to the chipped p28...i guarantee you that the chipped p28 is gonna make your car go faster, because the fuel/air is pumped up.

 

u can still run a stock p28 but it wont be stronger than a chipped p28.....

 

x2...x2...as long as you have the correct harness...

 

its all obd1 1995

 

Chipped or not a P28 wont throw a CEL if all sensors are connector correctly and functioning. A stock P28 does not however have the correct fuel and timing maps, redline etc to run a B16A optimally. Get it chipped with P30 B16A maps and you'll be fine.

 

i would recommend you get your hands on the correct ecu for your motor, see if you can get your hands on a p30. just my $.02