ECU Problems

[boost4life]

Hi there,

We have an P72 ecu for use on a 1997 Integra Type R. There are no modifications done to the car.

The latest version of the software has been installed and the USB Drivers have been updated.

The attached calibration has been loaded to the ecu and the car started with this calibration.

The car starts smoothly and idles normally for four to five minutes. There is however a check code 23 displayed in the DTC window. The knock sensor does not throw any codes with the standard ecu.

Then the engine starts very suddenly to hunt irratically and a message appears in the region of the task bar indicating that the USB device is unrecognized.

The indicator light on the ecu also turns from green to red and programming interface freezes.

The engine check light also flashes on and off in sync with the rise and fall of the rpm.

We went through the list of items to check in the "S300 Troubleshooting" sticky.

The J4 jumper is connected and the J12 is broken, the S-Manager shows online, the attached file was created from new using the "Stock US P72" map.

The calibration was loaded without incident and s-manager could datalog.

The plugs are NGK iridiums.

Another laptop was used and encountered the same problems.

Thanks in advance.

[Hondata]

You will need to test the ECU in another vehicle to narrow the problem down to either the ECU or adapter harness.

[Spunkster]

Is this a US or JDM P72?

[boost4life]

I will have to check the ecu's serial to verify whether it is USDM or JDM. As we had checked the jumpers and found that J12 was cut we had assumed that it was definately a USDM ecu.

I will find the number later this evening and post back.

I have come across a second ecu which has exactly the same problem which incidentally was bought around the same time.

I have applied a daily driven map used in another hondata to both ecus but they both react the same way. If one of the base maps is used, the same result.

The phenomenon does not seem to be related to temperature as the same happens whether or not the car is at operating temperature. One of the relays (not sure which one) clicks on and off with the rpm rise and fall.

It has recently been realized by the owner that unplugging the IAC valve prevents the ocurrence.

[boost4life]

The second ecu is a USDM P28. Could the problem be related to the idle control settings?

[Spunkster]

On a P28 you cannot have the knock sensor enabled as it does not have knock control.

You may have the plugs incorrectly plugged into things in the engine bay for the idle issue.

Without datalogs and calibrations that show the problem it is impossible to guess what you are describing.

[boost4life]

Last night we were able to perform the testing as was suggested in your first response.

We went to an OBD2 civic which drives daily on a hondata ecu. Left the conversion harness in place so everything aft of the ecu is known to be good.
Plugged each of the ecu's in and loaded the same map as the ecu which normally drives the car.

Each ecu idled the car for 3 to 4 minutes and shut down, exactly as they had done in the other two cars.

When the original ecu was replaced, all was well again. The original ecu is a P28, while the other two units are a P28 and P72.

Thanks again.

[Spunkster]

You need to provide a calibration and a datalog that shows the problem.

[Skunk2R]

I have exactly same problem.. With std JDM p72 ecu..Everything is perfect.. But when I use s300 with std p72 calibration..CEL 23-Knock Sensor..My Hondata is USDMp06converted vtec s300..I know p06 doesnot look Knock sensor..Anybody help me?

[Spunkster]

If the ecu does not have a separate circuit board c onnected via a ribbon calbe inside the ecu, then it does not have knock control and you must disable the knock sensor in the software (Parameters, Misc.).

[Spunkster]

Please post a datalog showing the knock error.