You know how when odb2 cars go to get emissions, the car is tested through the harness.

Odb1 car get tested through the tailpipe emissions.

Correct me if I'm wrong.

So if I go from a p72odb2 to a p72odb1 ecu, then when I go get my emissions done, they will have to test it through the tailpipe right?

 

First off, it's "OBD," not "ODB."

Testing procedures vary from state to state. Generally however, they go by the model year of your car rather than what sort of computer you have. If you put an older OBD1 computer into an OBD2 car and the smog station looks for such things, they will probably not pass you since the wiring has to either get hacked up or have a jumper harness installed in order to use it.

Every car gets its tailpipe sniffed. Do you have some reason that your car won't pass emissions? The only state where people tend to have any sort of problems is California.

 

Not yet anyways. I was planning on going NA, and in doing so I was going to be using a Hondata sys requiring me to go to a p72obd1 ecu. So I was curious about emissions testing.

I had a 93 accord that was obd1. It got it's tailpipe sniffed. I now have a 98 gsr. It DIDN'T get its tailpipe sniffed. The guy told me obd2 cars have all the data they need in the ecu and all they need to do is pull it out. Hence, he went straight to my wiring harness behind my console, hooked it up, checked the stats, and said I passed.

 

Hmm.

I don't know how the laws work where you are. I would wager a guess that if they want to pull data out of the ECU that would be done specifically based on model year since OBD2 was implemented across the board in 1996. If you convert an OBD2 car back to OBD1 then they're still probably going to want to scan the ECU. If you don't have the right ECU they won't be able to scan it and they might fail you..

The cost of getting an OBD1 ECU, a conversion harness and the Hondata conversion is a bit much. For an n/a application you could do fine with a V-AFC and then your OBD2 ECU is still intact if it does in fact need to be scanned or something for emissions testing.

 

I just wanted to put my two cents in here.
I'm not sure what the state inspections are like in GA, but here in Mass the system is pretty unfoolable. If your model car is not OBD II equipped from factory then the inspection machine will know it. Its not a matter of choice from the inspectors point of view, they merely do what the inspection machine tells them to do. OBD II was introduced in '96 model year cars so anything prior to '96 gets tailpipe emissions checked. (here in Mass its every other year for emissions testing) So pretty much no matter what ECU you put in, the inspection machine doesnt ask you to hook up the OBD II connector since the car isnt equipped with one. (according to its database)

Hope this sheds some light on the process. I am willing to bet that most states have a similar system if not identical for emmissions testing.

Shoofly
Acura Mechanic

 

FL=no emissions testing what so ever.

Good thing since my car would definitly fail.

 

if youre car is ORIGINGALLY an OBD-II equipped car, then when you smog it, you WILL HAVE to get it tested by OBD-II standards and procedures.... and if the smog stations has any inkling of what theyre doing (legally of course) then your car will fail being that its no longer OBD-II...

 

in case you didnt know
obd = on board diagnostics
just thought i would throw that out there

 

What you guys have said is pretty much what i was thinking.
Thanx.