Civic EG

what is the different in obd1 and obd2 and why does it matter?

On Board Diagnostics. Its what computer system runs which engines.

You have obd0 or "Pre-OBD"(correct term) which is a Mess and should be avoided at all costs(Normally on 88-91 Civics and Integras.) Its not uncommon for the Distributer to go out. I have friends who go through dizzys every 6-9 Months. To check engines code you have to pull out the ECU and look at a Flashing light. OBD0 also typically likes using Vacuum lines. Like I early said a Mess and should be avoided at all costs.

OBD1 Is the most popular OBD as its the easiest to reprogram your computer. Almost all hondas 92-95 Run OBD1. The 90-93 Accord are all OBD1 as well. OBD1 is Super Reliable and if something does go wrong its easy to check codes.

OBD2 has two sub versions, OBD2a( 96-98 ) and obd2b( 99-01+ ) After 01 Some Hondas went to CAN based computers and some stayed OBD2b for a while. Today all hondas use CAN based Comptuers.
OBD2 Does have good tuning options however most people will get a Jumper Harness to let them use OBD1 ECU's, Most of the time reprogramed into their OBD2a or OBD2b Cars.

You can take any Honda Engine OBD0,OBD1,or OBD2 and convert it to each other OBD's by exchanged Distrubtor, Fuel Injectors and Alternators with the correct one.

For example B20b's are only available in OBD2, you can easily convert it to OBD1 by using an OBD1 Integra LS Distrubtor(or using a DIY to swap guts with your OBD1 Dizzy) OBD1 Alternator from your D Series and your OBD1 Fuel Injectors. You dont need to worry about different injectors sizes as they are all the same, Honda just changes fuel pressure on different engines.

Hope this answers your Questions. I also edited the Title and made it a Sticky so it can help more Noobs.

ok man thank that what i wanted to know and if anyone else has any question about them feel free to post them because i'd like to learn more about obd's

Chrono,

Good explanation.
This should help me and many others to better understand "On Board Diagnostics".

Thanks.

to cut it short if you need cliff notes

its a year where basically they added a new 16 pin connector on cars 96+ EVEN SOME late model year 1995's came with it (non honda)

the ecu's for civics example are not the same, also SOME clips are different like the fuel injector clips, depending what model the IAT is not the same and nor is the IACV.

and they added a whole lot more SMOG bullshit.

its not possible to smog a 1996+ car w/ a OBD 1 computer (w/ using a jumper harness ofcourse)

then they added a bunch of useless crap like the crank angle sensor to make life living hell.

stay away from obd 2 its hell! imo

obd-0 / obd-1 ftmfw

0verb00st-ej2 wrote:to cut it short if you need cliff notes

its a year where basically they added a new 16 pin connector on cars 96+ EVEN SOME late model year 1995's came with it (non honda)

the ecu's for civics example are not the same, also SOME clips are different like the fuel injector clips, depending what model the IAT is not the same and nor is the IACV.

and they added a whole lot more SMOG bullshit.

its not possible to smog a 1996+ car w/ a OBD 1 computer (w/ using a jumper harness ofcourse)

then they added a bunch of useless crap like the crank angle sensor to make life living hell.

stay away from obd 2 its hell! imo

obd-0 / obd-1 ftmfw

I read threw this many times and still couldn't make since of it.

OBD-0 is aweful, It uses vacuum lines, Electronic parts die often and are expensive, Tuning is harder. Converting to OBD-1 is also much harder. Having a perfectally reliable obd-0 is quite hard to do. If any OBD will be hell it would be OBD-0/pre-odb

on OBD 1 and OBD 2 its super easy to swap bewteen standards with just a jumper harness, no more wires need to tied into to anything. Electronic parts dont die 6-9 months after they where replaced. Its much much more simple.

I'm sometimes jealous I dont have Obd2 as they have cool things for it. For example there is an iPad/iPhone app for see what your cars doing and do simple "tuning"(sure it doesn't do the word justice) and it only works on obd2 cars. Not sure how good the program is, however its quite cool and If I owned an obd2 car I would try it.

In Cali I'm sure its much more important as they monitor hondas very closely on what engines and electronics and emissions equipment comes and goes onto what cars/years.

not to be insulting, but most of your post has incorrect information in it.
Like honda didn't add a crank angle sensor in obd2, they moved it out of the dizzy where it use to be and put it in a crazy place. Next to the crank.

Also you can stay smog legal and be tuned on hondata.