Alright so this all started after I did my head gasket on my 97 civic dx. d16y7 is the motor I have. I replaced the head gasket and ever since it has run sporadically rough since. it only runs rough for like 10 seconds on start up sometimes or just out of random it will like bog down then run good again. once it does it though it runs great after. Also I had a check engine light pop on. The codes that are present are p0118 (engine coolant temperature sensor) p1381 (cylinder position sensor) p0113 (intake air temperature circuit) and p1509 (idle air control valve). I find it hard to believe that all sensors are bad as i think the car would run rough all the time if they all were bad. The only modification done to the motor is a aftermarket header. The only other thing is that the downstream 02 sensor is not plugged in as I need to get a new one. My question is really do you guys think that all sensors are bad? Or could it just be the missing 02 sensor?

Any help would be greatly appreciated.
Thanks Josh

 

Holy crap. You know when you get the O2 sensor installed you'll answer your own question.

Also, if you have a Y7 and you put on a header, where is the catalytic converter and 2nd O2 sensor?

 

the 2nd 0 sensor is the one missing. i though that was called the downstream 02 sensor sorry bout that. Anyway I eliminated the catalytic converter with the header which is 4-2-1. The second 02 sensor is right at the endd of the headerpipe.

 

Okay, understand how your car works. The second sensor is to check for the efficiency of the catalyst. You have no catalyst. You have no sensor. What do you think the ECU is going to do? It's still looking for the downstream O2 sensor to be doing it's job, which it isn't because it's not there. The ECU is going to treat it as if it's malfunctioning, throw a code, and whatever else it's programmed to do when it encounters such issues.

And If you're going to put on a header then convert everything over to the EX exhaust system, including the converter, and install the 2nd sensor.

 

Alright ill hook up the 02 sensor this weekend and see what happens. thanks for your input i appreciate it.

 

Argh! You have no catalytic converter!