1995 Accord ECU as Honda OBD1 protocol test box ?

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Originally Posted by ECU-MAN

While you are there, look to see if the engine has a VTP sensor, take photo's

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Bugger, I was there two hours before your post.

OK, yours has the VTEC wire in position D6, mine does not.
I didn't take a picture of the engine today, probably should have thought to do that, but it was yet another raining day here at the time so that's my weak excuse :)
I have the ECT and MAP plus the first 100mm of cable. Will wire up to the ECU soon. I have pressure and vacuum tool from setting up two stroke carburetors that might be able to measure the MAP output.

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nice work

I like the test bed :)

I should also say that the wiring is from a WAGON CD Accord VTI.

I think the wagons are made in the USA? where as sedans were jap??Often certain engines do not have vtec pressure switches in one country, but they do for other counties (for example AUDM f23a engines dont have vtec pressure switches, where as the f23a in the USA do have one).

So maybe there is a difference in this regard between q50 and q51 ecu?
As discussed, as you can see in my pic, there is the Vtec Solenoid and a Vtec pressure switch (VTP). Incase you didnt know, the solenoid is the thing that opens a passage for oil to active vtec, and the VTP is basically an oil pressure sensor, so if the oil pressure is too low, then the ecu wont allow vtec to engage. If the factory setup does not have a VTP, then it just activates vtec regardless.

Thanks ECU-MAN, just got a better picture to post up. I responded to your PM too.

The test bed, now with MAP and ECT fitted. I want to fit the ECT sensor in the side of a tin can so I can test it with hot water against a thermocouple probe (to verify the Arduino scaling and offset).

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Quote:

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Originally Posted by Dxs

I should also say that the wiring is from a WAGON CD Accord VTI.

I think the wagons are made in the USA? where as sedans were jap??Often certain engines do not have vtec pressure switches in one country, but they do for other counties (for example AUDM f23a engines dont have vtec pressure switches, where as the f23a in the USA do have one).

So maybe there is a difference in this regard between q50 and q51 ecu?
As discussed, as you can see in my pic, there is the Vtec Solenoid and a Vtec pressure switch (VTP). Incase you didnt know, the solenoid is the thing that opens a passage for oil to active vtec, and the VTP is basically an oil pressure sensor, so if the oil pressure is too low, then the ecu wont allow vtec to engage. If the factory setup does not have a VTP, then it just activates vtec regardless.

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I forgot to take a pic of the engine bay, but I did get one of the whole car and the VIN. Can the VIN be decoded to reveal the engine type/version ?
Attachment 29747Attachment 29748

Quick question for ECU-MAN. Do stock Honda MAP sensors like the one I have (PS-30) read positive (boost) as well as vacuum ?
I suspect maybe so, as I can get an increasing reading by pressuring the MAP (not much I don't want to damage it just yet).

I think they are good for 3 PSI, the ROM will throw a code as soon as it sees positive pressure.

That beast should have had a VTP (VTEC Pressure Switch) Its build date should be 94/95

The shop manuals graph pressure v voltage / temp v voltage for the sensors. I have added the graphs to the sensor test in the PGMFI Diagnostic DIY's I made

http://www.ozhonda.com/forum/showthr...ics-Code-3-MAP