I have a 2000 civic Si that I have tuned. Its using a obd-2 p28, hondata s200 system and running a max-rev kit. When the car was brought into my shop it came in with the stock ecu, stock everything. I installed the kit, the clutch, exhaust and hondata. At the same time the Hondata was installed I hooked my wideband fjo kit into the car. I tuned all the partial throttle, as well as the WOT/boosted maps via street and dyno. Everything was fine until at the dyno appointment was over I switched from the fjo wideband kit to the stock oxygen sensor. The car immediately threw codes 6, 7 and 10 which are coolant temp, intake air temp and tps. I had to switch back to the fjo wideband kit to get the car from the dyno to my shop. I field tested all the sensors with both continuity and voltage, all check out fine. I have never heard, or had any problem of this sort before in tuning the Hondata units. Hondata themselves claims a bad ground, but I cannot find any. Anyone have any suggestions, I am completely stumpped on this one....

 

Look in your Helms and also consider this:

All those sensors use the same ground (according to helms) and when you use the FJO, you are using the ground from the FJO and not the one from the ecu to the sensor (signal ground- green wire).

 

Are you sure your using the right tools?

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by boosted hybrid &raquo;</TD></TR><TR><TD CLASS="quote">I have a 2000 civic Si that I have tuned. Its using a obd-2 p28, hondata s200 system and running a max-rev kit. When the car was brought into my shop it came in with the stock ecu, stock everything. I installed the kit, the clutch, exhaust and hondata. At the same time the Hondata was installed I hooked my wideband fjo kit into the car. I tuned all the partial throttle, as well as the WOT/boosted maps via street and dyno. Everything was fine until at the dyno appointment was over I switched from the fjo wideband kit to the stock oxygen sensor. The car immediately threw codes 6, 7 and 10 which are coolant temp, intake air temp and tps. I had to switch back to the fjo wideband kit to get the car from the dyno to my shop. I field tested all the sensors with both continuity and voltage, all check out fine. I have never heard, or had any problem of this sort before in tuning the Hondata units. Hondata themselves claims a bad ground, but I cannot find any. Anyone have any suggestions, I am completely stumpped on this one....</TD></TR></TABLE>

sounds like an issue that could be with the conversion harness. check the harness obd1 side for pin d22, which is the ground for the aove mentioned sensors

 

Its not using a conversion harness, its the new p28 ecus that have the obd-2 style plug right on them. I realized that the fjo is getting a chassis ground, which is what I originally thought could be the issue with the stock harness. I will check it out today some more.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by boosted hybrid &raquo;</TD></TR><TR><TD CLASS="quote">Its not using a conversion harness, its the new p28 ecus that have the obd-2 style plug right on them. I realized that the fjo is getting a chassis ground, which is what I originally thought could be the issue with the stock harness. I will check it out today some more.</TD></TR></TABLE>

if u look closely in the hondata ECU the soldering is all over the place, it is porly done....... get a new ECU

 

I finally figured it out. I spliced into the green signal ground wire and ran a secondary ground wire to the chassis ground. This took care of the problem. If anyone runs into this problem, this is what you need to do.