So I've been trying to figure out what is causing my CEL #9, the first place I decided to go was the distributor. I replaced my autozone one with an oem td 44u, still getting the same code. Although the car seems to be running better...However the code persists, even after resetting the ECU. I guess now its time to check my jumper harness and all the connections...Any particular place I should start? BTW the car is a 1990 Civic Si with a GS-R from a 98 Integra, the conversion harness is from what I know an off-brand (non rywire). I believe all the wiring is correct though, as a well known tuner did the conversion when he tuned my car. The ECU is a chipped P28...

 

What is cel # 9?

 

Its a piston position sensor failure. The sensor either needs to be experiencing irregular input or have a short to throw the code. I replaced the distributor, thinking it was the sensor itself (plus I wanted an OEM one anyways). That didn't solve the problem, so now I guess it's time to check the rest of the circuit...

 

Is the mechanical timing/electrical timing set correctly?

 

 

Always run factory service manual troubleshooting before throwing money at problems. If you replaced the distributor it is more likely a wiring or ecu problem, definitely foolow the pages that bergercurits posted, but also make sure you download the fsm for the 98 gsr and the 1990 civic. The odds of having the same sensor fail on 2 diff distributors is rare, and in the 18 years I have been into hondas i have only seen one legit sensor failure in a distributor...but it was also a complete physical failure of the distributor...

 

Yeah sensor failure is a pretty rare thing from what I've read. My problem is probably the wiring itself, it was a quick job and looks pretty sketchy. I have a feeling it is just a bad connection...The car runs pretty fine other than having a check engine light (ran a 13.85 at 101mph at Lebanon valley)

 

Yeah that's all correct.

 

I had the same problem when I did the MPFI swap on my Civic STD. I changed the distributor and still had the same problem, CEL 9. Turned out to be the wire from the distributor to my ECU had a frayed connection. I discovered this by getting a multimeter and checking for continuity on the wires going from the ECU to the engine bay. For each ECU pin, I shook my wire harness in the engine bay and tried to see if the multimeter changed. When I got to the distributor ECU pin, the multimeter went crazy. Undid the wire bundle and found the problem. fixed my wire and the car has no problems.

 

I see this all the time with eBay bought ecu jumpers. Check pin d14 on the obd1 ecu plug side. There should not be a spliced wire. If there is cut it off. That's the o2 sensor wire. EBay jumpers are notorious for having this wire spliced with the distributor wiring

 

Sorry to bring the thread back from the dead, but I've found a fix that may be of help to others.

I have a USDM P91 which is throwing a code 9. I bench tested it with a Moates.Net Engine Simulator so I knew the fault was NOT a dizzy related problem.

Firstly, I was just fiddling around having a look and I decided to to connect a main capacitor to pin's B11 and B12 to help 'smooth' the signal. What do you know ... the problem disappeared!
Then I knew it was a signal issue, so I traced the pin B11 on the underside of the board which lead to a ceramic disc capacitor marked "102" at 'C4' on the top side ...

I replaced this capacitor and it now works perfectly.

Short version:
Trace pin B11 to the first capacitor you come across and replace it.