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Is your car a coverted manual, or is it a manual from the factory? Did you ever run a VAFC?

Manual from the factory, yes I did have a vafc. Why do you ask ?

Just was wondering what else we may have in common. I have the VAFC currently installed, but I converted my car from an auto to a manual.

My vafc is still in my car as well, as soon as I figure out how to get rid of #9 it will be gone. I have an idea, I just have to call some of my friends and borrow an oscilloscope.

I've got an oscope right now. Were you going to pull the CKP, TDC, and CYP signals from the ECU harness and then compare them to one from an OBD1 car?

I've got an oscope right now. Were you going to pull the CKP, TDC, and CYP signals from the ECU harness and then compare them to one from an OBD1 car?

Do it !!!! I want to see the results !!!!

Is this your factory distributor or, is it a replacement?

Here is what evans tuning says about CEL 9

My car has 100k km on it, the distributor is the original one that came with the car. The guy is correct but in our case it doesn't apply, we dont get a code using our P5P, it the distributor was messed up we would get a code when using P5P, so that's not the case.

I did some research on CYP sensors used in Honda cars and I found something of interest to us.

OBD1 Civic, Integra, Prelude and OBD2 Civic have the resistance of the CYP sensor pickup specified at 350-700 ohms. OBD2 Integra 500-1000 ohms and OBD2 Prelude 260-460 ohms.

I am assuming that the ECU is expecting to see a certain resistance across the CYP wires. As you can see from the above breakdown of resistance values OBD2 Prelude has the lowest resistance rating of all of them. I am just guessing that if the resistance of the OBD2 Prelude pickup was too low for a civic or integra obd1 ecu and it would see it as a malfunction and throw #9. Let's assume that the actual resistance values of the pickups are halfway in between the specified range. OBD2 Prelude would be seating at 360 ohms nominal, the other cars would be at 525 ohms and OBD2 Inetgra would be at 750 ohms. 360 ohms is just 10 ohms above the lowest specified threshold for the OBD1 cars. Now that could be a problem, ecu sees it as a bad sensor and throws a code. When it comes to OBD2 Integra, the value is high, maybe the ecu still accepts that value.I am planning to measure the CYP pickup resistance today, I will post my result later on. I will also try to trick the ecu so it sees a higher resistance.

Well I measure all the signals today with the Oscope. They didn't tell me much although I did record the voltage levels, and took pictures of the signals(ckp, tdc, cyp).

I also measured the resistance of the cyp sensor and it was about 400 ohms. The helms manual specifys 260-460 ohms for the 97-98 lude.

Let me know if you want to see the pics of the signals

I measured my sensor pickup as well, 378 ohms. I also put a 120 ohm resistor in series with the sensor pickup - still got #9.

Looks like you did some work as well. I would like to see the waveforms. Now we have to get hold of some obd1 waveforms and compare.

Well last night, I created a hybrid distributor. Luckily I have 2, OBD2 ecu's and 1, OBD1 distributor. I used the wiring harness from the OBD2 distributor, and the casting from the OBD 1 Distributor. I kept all the sensors In the OBD1 dizzy(TDC, CYP, CKP). I ran the TDC and CKP wires directly to the conversion harness, and wired the CYP sensor into the OBD2 dizzy wiring harness. I then started the car up with the OBD2 P5 ECU, and used the CKP and TDC sensors that are mounted near the crank. The car ran fine with no CEL's. I then ran the TDC, and CKP sensors from the dizzy to the conversion harness. I used the chipped JDM p72, and started the car, the ECU then continued to throw the CEL 9. I checked the wave forms from the OBD 1 dizzy, and from the OBD2 and the CYP signal is the same. The TDC , and CKP vary slightly. I plan to try and run my P5 ECU from the Dizzy sensors tonight to see if that works. I am goin to try an put a h22 based bin file on my eprom, and see if that effects this CEL 9. I have yet to run a h22 based bin file, so i will give that a try.

I was actually planning to get a OBD1 distributor and try the same thing you did. There has to be something in it, I don't understand why you would get a #9 if you were running a OBD1 distributor with OBD1 ecu, I thought about it for a while and I am puzzled, I have no idea what's going on. As for the H22 bin, I would have nothing to do with it, I ran a H22 bin and I got #9 every time.

UPDATE

I got a OBD1 distributor, made a conversion harness for it so it's plug and play, plugged my P06 in and no codes !!!