Hondata S300 Nightmare (Updated--Nightmare no more)

s300 and SManager software questions & answers
Aman
Posts: 12
Joined: Mon Jan 16, 2006 7:33 am

Hondata S300 Nightmare (Updated--Nightmare no more)

Post by Aman » Mon Jan 16, 2006 7:36 am

Since mid November I have been trying to get a Hondata S300 prepped P72 1994 ECU in my car. Simple enough you?d think. During the tuning process of this ECU it was found that the IAB circuit is not working, the massive 10 hp drop between 4400~5200rpm was a definitive sign. Strange I though, since the ?94 ECU, virgin, was working this summer when it was in my car. The ?94 ECU made the car run very rich so I stopped using it when gas prices went up.

I have a 1999 GSR, let?s call it mildly modified, to keep this short. I picked up a ?94 P72 ECU in 2000 and an obd 2>1 wire harness. I did a little test at the local drag strip, I ran basically the same time with both the stock ECU and obd1 ECU. So the thought in those days an obd1 was faster than an obd2, not true.
In my build up plan I still want to use the stock GSR dual runner intake so no change to a single runner type.
So in November I finally decided to take the plunge into getting the car tuned. Lets just say after about $1400 dollars I still don?t have a tuned car. $1400= used ecu, wire harness, S300, dyno time and I am still not finished.
The section of the power band that was tuned 5000 to redline looks great.

Has anyone experience any trouble like this?
Is it possible to damage the IAB circuit when installing the S300?
At one time I thought I had read there was a programming glitch or trouble in the IAB software in the Smanager, but unfortunately I can seem to find that information.
Last edited by Aman on Sat Feb 18, 2006 5:36 am, edited 1 time in total.

User avatar
Spunkster
Site Admin
Posts: 17861
Joined: Fri Sep 20, 2002 5:06 pm
Location: Hondata
Contact:

Post by Spunkster » Mon Jan 16, 2006 10:56 am

Have you tried inverting the IAB output? Over the years, Honda has inverted the way the IAB works.

Aman
Posts: 12
Joined: Mon Jan 16, 2006 7:33 am

Post by Aman » Mon Jan 16, 2006 12:59 pm

The IAB output. Wouldn't I had trouble with this before the ECU had been modified for the S300?
Is this something that can be done in the software or is the a wiring swap on the wire harness?

User avatar
Spunkster
Site Admin
Posts: 17861
Joined: Fri Sep 20, 2002 5:06 pm
Location: Hondata
Contact:

Post by Spunkster » Mon Jan 16, 2006 1:04 pm

see if the runner is opening or not

Aman
Posts: 12
Joined: Mon Jan 16, 2006 7:33 am

Post by Aman » Mon Jan 16, 2006 2:43 pm

Currently the car is running the stock OBD2 ecu and the IAB's move. When the '94 ECU with out the S300, was in the car the IAB's also functioned properly. They stop functioning properly after the S300 was inserted to the ECU.

User avatar
Spunkster
Site Admin
Posts: 17861
Joined: Fri Sep 20, 2002 5:06 pm
Location: Hondata
Contact:

Post by Spunkster » Mon Jan 16, 2006 5:58 pm

Have you tried inverting the IAB output?

Can you post he calibration you are using?

kaj
Posts: 98
Joined: Mon Nov 21, 2005 4:47 pm

Post by kaj » Mon Jan 16, 2006 10:14 pm

Spunkster wrote:Have you tried inverting the IAB output?
you need to check this before proceeding.
Last edited by kaj on Thu Jan 19, 2006 12:19 pm, edited 1 time in total.

RMS
Posts: 212
Joined: Thu Nov 20, 2003 12:35 am
Location: Visalia, CA

Post by RMS » Mon Jan 16, 2006 10:38 pm

obdII iab will not work with the obdI p72 without wiring mods. inverting the output will not work.

also, iab has VERY VERY LITTLE effect on 1/4mile times.

this IS NOT A HONDATA ISSUE. any qualified honda tuner should have warned you of this before you visited the dyno. obdII 'teg ecus send a 12Volt signal to the iab to CLOSE them. obd I 'teg ecus send a GROUND signal to the iab to close them. you will have to add a relay to your jumper harness to correct this problem. if you were using an obdI civic ecu we could add iab and fix the polarity issue within the ecu. nothing but the relay fixes the p72 though.

IAB wire from ecu goes to COIL side of relay.
12 volt ignition goes to other side of COIL and to COMMON.
N.O. goes to iab solenoid.

hope that helps
RaVer Motorsports (559) 733-4711
ravermotorsports@earthlink.net

kaj
Posts: 98
Joined: Mon Nov 21, 2005 4:47 pm

Post by kaj » Tue Jan 17, 2006 3:28 pm

...
Last edited by kaj on Thu Jan 19, 2006 12:18 pm, edited 1 time in total.

Aman
Posts: 12
Joined: Mon Jan 16, 2006 7:33 am

Post by Aman » Wed Jan 18, 2006 5:15 am

So let me get this straight. There is no way the OBD1 ECU was operating the IAB circuit. Then before the ECU was modified how come I could hear a change in the engine when the butterfly valves opened @ 5600rpm just like with the Stock OBD2a ECU?
Secondly why is this the first time in 6 years I have ever heard that additional modifications are required to the OBD1 ECU to get the IAB circuit to work? Should this little bit off very important information be mention someplace on Hondata?s web site?
I might have to question the 1/4 time reply, by the look of the dyno 10 less ft-lbs of torque between 4200~5200 would definitely slow me down in 1st and every time I shift gears. The rpms drop back in to that exact location in the power band.
I just want to get my car running with a Hondata ECU.

kaj
Posts: 98
Joined: Mon Nov 21, 2005 4:47 pm

Post by kaj » Wed Jan 18, 2006 5:31 pm

Aman wrote:So let me get this straight. There is no way the OBD1 ECU was operating the IAB circuit. Then before the ECU was modified how come I could hear a change in the engine when the butterfly valves opened @ 5600rpm just like with the Stock OBD2a ECU?
Secondly why is this the first time in 6 years I have ever heard that additional modifications are required to the OBD1 ECU to get the IAB circuit to work? Should this little bit off very important information be mention someplace on Hondata?s web site?
I might have to question the 1/4 time reply, by the look of the dyno 10 less ft-lbs of torque between 4200~5200 would definitely slow me down in 1st and every time I shift gears. The rpms drop back in to that exact location in the power band.
I just want to get my car running with a Hondata ECU.
while you are drag racing you would, most likely, never see 4200~5200 rpm. so, even if you were down 10ft lbs or torque, you wouldn't notice.
Last edited by kaj on Thu Jan 19, 2006 12:17 pm, edited 1 time in total.

Aman
Posts: 12
Joined: Mon Jan 16, 2006 7:33 am

Post by Aman » Thu Jan 19, 2006 8:19 am

I am basically at the point now of asking myself what are my options. First if I had known additional work was required to get the OBD1 ECU I may not have selected the S300.
Secondly I am very disappointed that my tuner had no knowledge of these issues. I am also extremely disappointed that HONDATA has no mention of these issues involving the P72 ECU on there web site.
I understand that most people change to the single runner intake manifold so problem really wouldn?t be an issue to them. But I am not after some high revving high horsepower engine. I just want a more balanced street car. Considering the car already makes nearly about 125ft-lbs in a relatively flat curve, I wanted to continue to build on this strength of my engine.
One clarification/question the OBD1 ECU, prior to the addition of the S300 and the secondary butterflies worked. How is that possible?

Any suggestions?

kaj
Posts: 98
Joined: Mon Nov 21, 2005 4:47 pm

Post by kaj » Thu Jan 19, 2006 10:17 am

**edited 'cause i was stupid.
Last edited by kaj on Thu Jan 19, 2006 12:16 pm, edited 1 time in total.

Aman
Posts: 12
Joined: Mon Jan 16, 2006 7:33 am

Post by Aman » Thu Jan 19, 2006 11:45 am

[quote="RMS"]obdII iab will not work with the obdI p72 without wiring mods. inverting the output will not work.

also, iab has VERY VERY LITTLE effect on 1/4mile times.

this IS NOT A HONDATA ISSUE. any qualified honda tuner should have warned you of this before you visited the dyno. obdII 'teg ecus send a 12Volt signal to the iab to CLOSE them. obd I 'teg ecus send a GROUND signal to the iab to close them. you will have to add a relay to your jumper harness to correct this problem. if you were using an obdI civic ecu we could add iab and fix the polarity issue within the ecu. nothing but the relay fixes the p72 though.

IAB wire from ecu goes to COIL side of relay.
12 volt ignition goes to other side of COIL [u]and[/u] to COMMON.
N.O. goes to iab solenoid.

hope that helps[/quote]

What?? The above quote reads to me that more modifications are needed to the wire harness that I have to run an OBD1 ECU on my 1999 GSR. The issue I have is that I have never heard that additional modifications are required to get a OBD1 ECU to work in an OBD2 car. It also says that the OBD1 ECU wouldn't run the IAB in my car but it did. So can anyone explain that?
I have another Stock '95 OBD1 ECU that I am going to test in my car. From what I have read the IAB ciruit will not work in my car, but it did with other other OBD1 ECU.

kaj
Posts: 98
Joined: Mon Nov 21, 2005 4:47 pm

Post by kaj » Thu Jan 19, 2006 12:15 pm

Aman wrote:

What?? The above quote reads to me that more modifications are needed to the wire harness that I have to run an OBD1 ECU on my 1999 GSR. The issue I have is that I have never heard that additional modifications are required to get a OBD1 ECU to work in an OBD2 car. It also says that the OBD1 ECU wouldn't run the IAB in my car but it did. So can anyone explain that?
I have another Stock '95 OBD1 ECU that I am going to test in my car. From what I have read the IAB ciruit will not work in my car, but it did with other other OBD1 ECU.
i just re-read the whole thread. my mistake. i had no idea that OBD-II IAB would not work when using an OBD-I ecu. interesting.
i've never messed with an OBD-I gsr. hmmmmmmmmmmmmmmmmmmmmm.

yes. i would imagine your tuner should have known this.

assuming what RMS said about the different signals is correct ( i must say the guy knows his electronics ), then i have no idea why the other OBD-I ecu worked your IAB. are you sure you weren't hearing vtec?

worse comes to worse, it sounds easier to modify a civic ecu than to run relays. if not easier, cleaner fo' shizzle.

sorry for the earlier comments. i was the one that needed to pay closer attention to RMS's post :oops:

Locked