Honda ecu chipping problems - Fuel Economy, Hypermiling, EcoModding News and Forum

faberfiber_civic · 03-28-2009, 11:37 AM

I have a 97 civic ex d16 auto tranny obd2 ecu. I want wanting to put a obd1 ecu in it but I cant find any thing that supports auto trans. civics. Anyone know of anything? Thanks

hummingbird · 03-28-2009, 12:51 PM

Just curious... why this 'planned regression'?

faberfiber_civic · 03-28-2009, 01:17 PM

I am wanting to put obd1 in place of my obd2 because the obd2 I have heard theres a lot of rectrictions and the obd1 seems to have more available, also more tuner freindly.

cfg83 · 03-28-2009, 02:59 PM

faberfiber_civic -

Quote:

Originally Posted by faberfiber_civic

I am wanting to put obd1 in place of my obd2 because the obd2 I have heard theres a lot of rectrictions and the obd1 seems to have more available, also more tuner freindly.

I know what you mean. I think I am lucky in the sense that my car is a 1999 with basically "circa 1996 obd2" firmware. I've heard that newer ECU/PCMs are just "too smart for their own good" when it comes to ecomodding, and will fight with you. The older stuff can be "tricked" into getting better MPG.

The drawback for me is that there is no real "tuner culture" for my Saturn S-Series. All the chips are soldered onto the ECU/PCM. The only way to modify the ECU/PCM is through the dealer, and they won't do custom stuff. There is one for my car, but it's maybe $300, you have to mail your ECU/PCM to them for them to program, and it's performance-centric.

CarloSW2

rkcarguy · 03-28-2009, 07:06 PM

I'm kicking around doing the same thing to my wifes car, but for the reverse reason you are. Her A/T is getting tired and all the engines from Japan even EK's have the cable kickdown automatic instead of the electrically controlled one. I'm searching for info on this as well, I think if you get a OBD-1 auto ecu and have the tranny to match it will work, but otherwise your out of luck. I don't think the USDM OBD-1 ecu has the guts to run all the elect crap on the OBD-2 auto trans.

Christ · 03-29-2009, 08:09 PM

The Honda ECU's have the chips soldered in too, chipping them requires taking out the old ROM and replacing it with an EPROM of equal or greater value.

With OBD-1, the difference between AT and MT is a few resistors on the main board. (For Honda.)

RKcarguy - watch your local laws for now, WA has many Eco-measures in place that are kind of swap-proof... In fact, right now, in Spokane, Washington is the leading edge of the anti-phosphate movement. (Green dishwashing detergents).

Christ · 03-29-2009, 08:10 PM

Also - you can tune your ECU (hi-po or hi-mileage, whichever...) with CROME, UBERdata, TurboEdit, and a few others. I can't give the sites for them though, as that would be advertising, and it's borderline legal to modify an OBD-II vehicles Engine Control Systems, so I can't help anymore than that.

SVOboy · 03-29-2009, 08:34 PM

Quote:

Originally Posted by Christ

The Honda ECU's have the chips soldered in too, chipping them requires taking out the old ROM and replacing it with an EPROM of equal or greater value.

With OBD-1, the difference between AT and MT is a few resistors on the main board. (For Honda.)

RKcarguy - watch your local laws for now, WA has many Eco-measures in place that are kind of swap-proof... In fact, right now, in Spokane, Washington is the leading edge of the anti-phosphate movement. (Green dishwashing detergents).

Since when do you need to remove the stock prom on an obd1 board?

OP - don't waste your time, you won't get much out of it if you're going for fuel economy.

Christ · 03-29-2009, 08:36 PM

You may not need to on an OBD-1, I'm still stuck on OBD-0 for most things.

SVOboy · 03-29-2009, 08:52 PM

Ah, okay. You're right then for the obd-2 honda ecus. The obd1 ecus came with a separate prom spot that you could connect a jumper to to use, bypassing the stock chip (which was not an eeprom).