whats the difference between obd0,1,2. do they function different or are the plugs just different. no matter what your car is, when doing a swap, cant you just take the engine, ecu, and wiring harness and switch them all out? i have two 89's, one a crx si and a hatch dx auto. the crx has a sohc zc in it and its lil fun car but i wanted to swap that for something different, like a vtec d or any b series. but someone told me have fun converting the obd1,2. if i do a swap i want it to be from a usdm, ca car so i can get it all legalized. ive heard of conversion harnesses what do those do exactly?

 

obd2 96 and up
obd1 before 96
obd0 90 and before

 

thanks for that lil tidbit, but that doesnt explain reasons why everyone hates to convert or says its a bitch....i figure they changed for a reason (better?) id like to find out.

 

the later the year the more wiring you have to do, the more sensitive the onboard diagnostics system gets, i.e. obd2 has trouble codes for misfires for every cylinder as in obd1 doesn't have it

they say its a bitch because of all the wiring

 

are senors and engines interchangible

 

some are some arent due to the clips being different

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by bugster &raquo;</TD></TR><TR><TD CLASS="quote">...i figure they changed for a reason (better?) id like to find out.</TD></TR></TABLE>Government required the engine-control system to be able to detect (by itself) whether the emmissions systems were still working. For example an OBD-1 system has no way of 'knowing' whether the cat is working, or even whether it's still installed.