95-D16Z6-GIRL

1995 Honda Civic EX
D16Z6

Sorry this is long.

Ever since my engine has been rebuilt I have had a CEL for the Engine Coolant Temperature Sensor. I have about 4K on the rebuild. I had the head and the block done at a machine shop and had them return my motor to me with all internals set. New everything (gaskets, water pump, etc.) I replaced every last sensor on this while I finished putting everything back together. ALL new sensors for the entire motor. All three coolant temperature sensors have also been replaced along with a new thermostat. Yet I’m still throwing this CEL. I’ve checked the code and thankfully it’s just this one, but why? Pretty much everything on this motor is new.

It started as an auto and I did a manual swap during the time of the rebuild. I am still running the same ecu and it was only opened to install a jumper wire to trick the ecu into not looking for the knock sensor (for the trans swap) but otherwise it’s unmolested. All of my wires on the harness look good. No corrosion and nothing is frayed. The only thing I’ve read about that I haven’t done yet is test the connection at the ecu with my multi-meter for power. That is my plan tonight after work.

The main reason for writing this post is because I have searched multiple forums for a few days only to find generic “your head gasket is blown” bs or to replace parts which I’ve already done. I have no leaks anywhere on this car.

As of Sunday March 7th I replaced the engine coolant temperature sensor again, thinking I had a faulty sensor, while I was there I also replaced the sensor on the head that tells the gauge what’s going on. I did not re-replace the fan switch on the thermostat housing. I re-bled the coolant system first by a gravity bleed with the cap off, then by the specs in my FSM, which is with the car level, radiator cap halfway on and adjusting the bleeder valve. While doing this, the fans still did not kick on after 30 minutes of cycling. My temp gauge rose just above half and I gave up, shutting the car off after 40 minutes. I know my fans have power and work. Why can’t I seem to get all the air out of this system?

I have also had trouble starting this car in extreme cold. I live in St. Louis and we just had a really cold February. It would take 10-15 tries to get it to turn over only after sitting all night in extreme cold. I think my tps sensor may be bad as, the throttle response is lagging upon startup (when cold) so when I try to give her some throttle, she will sometimes die, again, only within the first few minutes of starting when cold.

Driving conditions are great with this car. The motor is strong, just these little things that are making things difficult. This morning on my way to work I noticed the temp gauge rising to “warm” faster than normal. I kept thinking, “I know you’re still cold. Why are you telling be you’re warming up when you haven’t been running for 5 minutes yet”

TomCat39

Have you followed the troubleshooting flow chart in the FSM for code 6?

I'm going to watch your thread as I just got code six after moving the sensor over to the head I just put on my car.

I plan on doing the ecu reset procedure and see if it returns, then follow through with the ohms and continuity checks the FSM goes through for code six in the fuel/emissions section.

I did forget to connect my valve cover ground strap and started the car when I went to burp the coolant system. Not sure if that relates as I haven't looked at the circuit yet as I just discovered the code last night when I went to time the car.

If you figure out your circuit issue, please do report back what your issue was and the resolution so others can benefit (myself included).

Thanks. And good luck.