iv been searching through countless threads and cant seem to find any help on this problem

i have a 00 teg gsr , i have used 2 diff obd2b to obd1 wiring conversion harness' ...
i have 2 diff p72 obd1 ecus .

car starts up ... the idle never seems to stabalize , sounds like misfires. and kind of seems powerless.
also there is a strong gas smell/exhuast smell

each time i put the ecu on i let it warm up , idle goes up , surges and then drops trying to pick its self back up

anyone have this prob ? i tired it on a diff 00 teg gsr and it did the same thing. iv been searching through countless threads for any answers i can find. so far i havnet a clue.

if anyone can help me out that would be great
thanx for your time

 

All you need to do is disconnect the EVAP sensor and your problems SHOULD go away.

 

Oh yeah, and from what I gather....... when it is warm/hot outside on cold start up it idles fine. It is when you warm start it or cold start it when it is cool/cold outside is when there are rough idle issues. That happened to me first hand and I think it is common knowledge now.

Try searching Kenji in the archives for more info. Your welcome!!

 

u have to give ur ecu time to relearn everything about ur car.. when u have a new wiped ecu.. u have to drive it for like 500 miles before it learns correct idles.

try taking it for a ride for a week.. turn on ur a/c for half hour.. then turn off.. then turn on heater.. then drive with ur headlights.. etc.. u have to excercise ur accesories while ur driving ur car for your ecu to learn..

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by jh2586 &raquo;</TD></TR><TR><TD CLASS="quote">u have to give ur ecu time to relearn everything about ur car.. when u have a new wiped ecu.. u have to drive it for like 500 miles before it learns correct idles.

try taking it for a ride for a week.. turn on ur a/c for half hour.. then turn off.. then turn on heater.. then drive with ur headlights.. etc.. u have to excercise ur accesories while ur driving ur car for your ecu to learn..</TD></TR></TABLE>

i will take her out for another spin, i did let her warm up and drove around the block, just seemed like it didnt want to do much. when i reconnected the obd2b ecu , started right back up fine thanx for the suggestion i ll give that a try

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Comp97GSR &raquo;</TD></TR><TR><TD CLASS="quote">All you need to do is disconnect the EVAP sensor and your problems SHOULD go away.
</TD></TR></TABLE>

really ? just take the plug off or actually remove it and plug the hole in the manifold. i will give this a try tomarrow , is there anymore info you can provide on this on why this happens or would work .. .thanx !

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Comp97GSR &raquo;</TD></TR><TR><TD CLASS="quote">Oh yeah, and from what I gather....... when it is warm/hot outside on cold start up it idles fine. It is when you warm start it or cold start it when it is cool/cold outside is when there are rough idle issues. That happened to me first hand and I think it is common knowledge now.

Try searching Kenji in the archives for more info. Your welcome!! </TD></TR></TABLE>

the rought start didnt seem to go away hah that is why i started searching and looking for answers. i would tap the gas after i let her warm up and the idle would go down then come back up and hang around 1500 then drift down to 750 then go down from 750 to 500 for a bit then go back up several times. sometimes the idle would stay around 750 but the car just seemed to vibrate like it was havening troble dong it. thanx for the info ! anything else !

 

Unplug the sensor, thats it.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by jh2586 &raquo;</TD></TR><TR><TD CLASS="quote">u have to give ur ecu time to relearn everything about ur car.. when u have a new wiped ecu.. u have to drive it for like 500 miles before it learns correct idles.

try taking it for a ride for a week.. turn on ur a/c for half hour.. then turn off.. then turn on heater.. then drive with ur headlights.. etc.. u have to excercise ur accesories while ur driving ur car for your ecu to learn..</TD></TR></TABLE>

WOW, that is the biggest load I have ever seen. Just so you know, to PROPERLY reset an ecu you need to:
1. Remove the fuse or disconnect the battery for 30 sec.
2. Start the engine (without accessories on and without touching the throttle)
3. Allow the engine to idle at least 15 min.


After you unplug the EVAP sensor and reset the ECU doing the above, come back and let us know.


EDIT: Added this to explain. Yes it is a P28 ecu BUT remember that going from OBD2-OBD1 is the issue here.


"The P28 ecu turns on the purge control solenoid at idle, that means a large vacuum leak. On the D16 SOHC engine, the purge vacuum source is ported vacuum coming off of the throttle body, as opposed to the type-r which uses straight intake manifold vacuum. The type-r ecu only allows purge control activation above a certain rpm/manifold pressure (I'm not sure which, I would have to look it up ). The big vacuum hose going to the purge control valve on the firewall is where leak is. Unplug the electrical connection to that valve and see if you still get the symptoms. Or pinch the hose with needlenose pliers. Good luck."

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Comp97GSR &raquo;</TD></TR><TR><TD CLASS="quote">

WOW, that is the biggest load I have ever seen. Just so you know, to PROPERLY reset an ecu you need to:
1. Remove the fuse or disconnect the battery for 30 sec.
2. Start the engine (without accessories on and without touching the throttle)
3. Allow the engine to idle at least 15 min.


After you unplug the EVAP sensor and reset the ECU doing the above, come back and let us know.


EDIT: Added this to explain. Yes it is a P28 ecu BUT remember that going from OBD2-OBD1 is the issue here.


"The P28 ecu turns on the purge control solenoid at idle, that means a large vacuum leak. On the D16 SOHC engine, the purge vacuum source is ported vacuum coming off of the throttle body, as opposed to the type-r which uses straight intake manifold vacuum. The type-r ecu only allows purge control activation above a certain rpm/manifold pressure (I'm not sure which, I would have to look it up ). The big vacuum hose going to the purge control valve on the firewall is where leak is. Unplug the electrical connection to that valve and see if you still get the symptoms. Or pinch the hose with needlenose pliers. Good luck."</TD></TR></TABLE>

p28 ? im using the p72

edit: i read it too fast haha

cool tomarrow i will get out there and do jus that thanx for the info !

 

Heres some more food for thought from another site. My question is, do you have the proper pig-tail?

From the Helm service manual (from the '98 & '00 manuals and I believe applies to all OBD2 P72):

- With engine running, engine speed below 5,750 rpm: battery voltage (12 V)
- With engine running, engine speed above 5,750 rpm: 0 V

It my understanding that the OBD1 P72 activates the IAB with a ground signal, either before or after 5750. I’m still figuring out the details myself. But that means your IAB is always locked in the high rpm position since it doesn't have a 12 V signal below 5750 like it is supposed to.


Also another thing to watch out for, I purchased a OBD2B -&gt; OBD1 conversion harness for my ’00 GS-R and just noticed that there isn't a wire or even a pin connected to the IAB pin location, for a OBD2B, pin B16 (pin A26 for OBD2A). I guess its time to shop for another harness.
Anyone need a OBD2B -&gt; OBD1 conversion harness that doesn’t need IAB?

 

IAB??

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by 00IntegrAllmotoR &raquo;</TD></TR><TR><TD CLASS="quote">IAB??</TD></TR></TABLE>

intake air bypass also known as secondaries in the intake manifold

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Comp97GSR &raquo;</TD></TR><TR><TD CLASS="quote">Heres some more food for thought from another site. My question is, do you have the proper pig-tail?

From the Helm service manual (from the '98 & '00 manuals and I believe applies to all OBD2 P72):

- With engine running, engine speed below 5,750 rpm: battery voltage (12 V)
- With engine running, engine speed above 5,750 rpm: 0 V

It my understanding that the OBD1 P72 activates the IAB with a ground signal, either before or after 5750. I’m still figuring out the details myself. But that means your IAB is always locked in the high rpm position since it doesn't have a 12 V signal below 5750 like it is supposed to.


Also another thing to watch out for, I purchased a OBD2B -&gt; OBD1 conversion harness for my ’00 GS-R and just noticed that there isn't a wire or even a pin connected to the IAB pin location, for a OBD2B, pin B16 (pin A26 for OBD2A). I guess its time to shop for another harness.
Anyone need a OBD2B -&gt; OBD1 conversion harness that doesn’t need IAB?</TD></TR></TABLE>

wow thats some good info, had no clue it wouldnt run the iab

what brand of harness did you have ? or do you have i should say ?

 

Boomslang, w/a P28 soon to have a S200 wired to it. Did you try the evap sensor?

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Comp97GSR &raquo;</TD></TR><TR><TD CLASS="quote">Boomslang, w/a P28 soon to have a S200 wired to it. Did you try the evap sensor?</TD></TR></TABLE>

not yet iv gotta go charge the battery hah been sitting too long, i had used my gf's battery yesterday hah . first harness i had was the boomslang , my second is rywire (use to be made by blown90hatch) i ll post back when i get that battery charged up so i can see if that evap works that prob out. btw thanx for all the information

 

Not a problem. If you are still having an issue afterwards, (though I doubt it) I can give you a link to some ECU info.

 

hey can i get that link cause my obd1 ecu is doing that too.