I’ve been chasing this issue with code P1381 CMP sensor a intermittent interruption. So I bought this car a few months ago now and it was driving fine until I came back from a trip about 1 and a half away and the next day I got the code. So I replaced the distributor as everyone says to do. I took off the negative terminal to my battery and unplugged the ecu fuse for 30 minutes. Code went away, I did a drive about 100+ miles round trip with about a 5 hour period the car was shut off in between that and it fired up no issues. It sat for a week and now I started it up today and the code has came back. I have since replaced plugs, cleaned iacv, and I also did a ohm reading on both the old distributor (which was aftermarket) and it read .394 ,When I put the new ( oreilly) distributor in it read .394 also. So I’m confused and stuck and would like to enjoy the car.

 

Did you do the ohm reading on the yellow and black wire going to the distributor (or the wire colors that match yel and blk on the wire harness)?

You may want to try the same ohm reading at the connector plugging into the PCM. The wires go to connector C on Pins C4 and C14. Also check the corresponding PCM pins to see if they are loose or corroded.

 

When I did the ohm reading test I did it on the distributor side of the 4 prong plug pig tail. I also checked the car harness side and it read completely different from the distributor, I can’t remember exactly what the reading was but it was way off from what the distributor ohms read. That being said I’ve been reading up on forums and I hear 2 sets of ohm readings that I should be seeing and they are 300-700 and 800-1500 and I would like to know which ohm reading is for my model. I have a 96 accord wagon lx with the f22b2 engine. Automatic if that helps also. I’m handy with cars and I know how to turn a wrench but electrical with cars is something I’m not so good at but would like to learn. For my vehicles I usually get the service/repair manual from the auto parts store so I can steer away from posting on forums but they didn’t have one at my local oreilly so I’m stuck.

 

Also I’m in the process of moving which is why I fired up the car the other day because I had packed some of my belongings in it to move to the new house and it went off again. I don’t have access to the car currently because I ended up just driving it to the new house and leaving it there. I will be back there this weekend and for good so I will get those ohm readings at the car harness side again and make sure to also get the readings from the pcm connector side. Also is there a way to check the pcm to see if it’s bad? And if it is, is there a way to repair it? The pick n pull I live by charged me about 160 bucks last time I got an ecu from them and I’m really low on funds and would like to get this resolved as cheap as possible.

 

800-1500 ohms in the 96 shop manual I have.

I'm not sure if you measured the resistance with the connector unplugged or plugged in.

The resistance reading with the distributor unplugged should be in that range on the distributor side of the harness. The PCM side should give a different reading, because you are reading the resistance on the PCM. Unplugging at the PCM and measuring the resistance can identify a problem with the wires between the distributor and PCM. Hope this makes sense.

I'm not a huge fan of aftermarket parts even though I use O'Reillys for some items. I typically go with used/junkyard parts on items that typically don't wear out. First check the resistance at the PCM. You may want to price a used distributor and a used PCM from the u-pull-it place to get an idea of potential costs.

 

Thank you for the correct reading. So when I did the ohm reading test. I unplugged distributor pigtail and put my 2 leads where the (black and yellow) wires meet with the distributor ( my distributor has different wire colors) which the distributor pigtail read .394 on both distributors, then I still left the distributor unplugged and checked the actual black and yellow wires on the male connector that plugs into the distributor ( the engine harness) which read way higher then the distributor reading I got. Can’t recall exactly what that ohm reading was. But never got to unplug the pcm side and do it that way. So when I do the ohm reading on the pcm connector do I leave the distributor plugged in or do I unplug said connector.

 

You will leave the distributor plugged it, because the resistance spec is for the sensor inside the distributor.

 

Okay thank you, so the ohm reading that I did have when I unplugged the distributor and did the test directly on the distributor pigtail was not the correct way of doing it?

 

Also I read back on when you said the pcm reading should be different, well what’s the ohm reading I should be getting from the pcm side? Is it still the 800-1500?

 

The distributor test is the correct way. The test at the PCM connector with the PCM unplugged and distributor plugged in should give the same reading. If not, then you have a problem in the wires from the distributor connector to the PCM. This is just an additional test to possibly narrow down wiring.

The PCM side does not have a resistance spec, because the PCM reads the signal and doesn't have a resistance spec.