Car is a 99 Civic EX, B18C1 Swap. Harness is OBD2B and ecu is OBD2A P72 with a conversion harness. So I swapped in a new engine harness the other day, or got help swapping one in I should say because my old one was hacked up. Now my car is basically running like crap. Here are the symptoms:

Cold startups (after a few hours of sitting) are very crappy, takes it a few seconds to start. When I get it started it runs like it's going to die and when I give it gas it hestitates a lot and acts like it wants to die, and it even did die one time. After about 20-30 seconds it stops with the hesitation for the most part. I also kind of smell gas in my garage but I don't know if it's related.

After a few min it idles steadily around 1700 RPM. Can't figure out why, assumed maybe a vacuum leak but I can't find anything. There could be something that I'm missing but not sure. I don't know where every vacuum line is.

The main things that were hacked up on the old harness were the distributor, which honestly I don't get why, but it was all rewired, the speed sensor, and the injectors. Which makes me think theres something odd about this distributor. There's nothing hacked on the distributor now though so not sure why there would be a problem with it.

Car also feels kind of sluggish. I could be paranoid but I feel like I've lost some power.

Here are the codes that I'm throwing:

P0117: Engine Coolant Curcuit Low Input

P0500: Vehicle Speed Sensor Malfunction

P1337: Control Ignition System or Misfire

Now one thing I did notice is that the bulb for the CEL was missing. Must have been from the previous owner. So I put a new one in the other day. Who knows what codes I was throwing before I did the harness swap, so I don't know what could have been affected by swapping the harness. All I know is the car was running fine as far as I know before putting in the new harness. But anyways those are the codes that I'm throwing now for sure. Other than the speed sensor (which I know doesn't work because the clip on the harness is broken and I need to wire in a new one), what do the other codes mean? I don't know what exactly I should be looking at and I'm getting really irritated with the bad startups, lack of power, and really high idle. Thanks for anyone that helps.

Please don't suggest that I clean my IACV because I know that's not it. The car ran fine before swapping in this harness. Please answer if you have logical ideas about how swapping a harness could affect my car like this.

 

any ideas?

 

P0117 - bad ECT sensor or wiring (2-wire sensor below the distributor)
P1337 - bad CKF sensor or wiring (CKF sensor is next the crank gear behind the lower timing belt cover)

Are these sensors plugged in? Have you checked the wires?

 

engine coolant temperature will definitely do this check it and make sure it is connected clean and no wires are broken

 

Thanks. I'll check these things out tomorrow.

 

Figured it out.

P1337 was thrown because the sensor behind the crank pulley was not plugged in.

P0117 was thrown because the vtec solenoid sensor and the ECT were switched around.

Here's a reference for anyone who has an ECT problem. Having code P0117 for ECT caused my car to have a very high steady idle. Also caused cold engine starts to be very crappy by being very hesitant and sputtery for a minute or so. The car also seemingly ran rich, but not 100% positive that it was.

 

glad you figured it out.