fliplyricist1

Weird stuff.

Was on a casual drive last week when the car suddenly died on me (pressed gas pedal and it felt like the car wasn't in gear). First the engine oil light, followed by the battery light, then the check engine light. Tried to turn it over but nada. Suspected alternator (have blown an alternator before), so I used a portable jumpstart kit and it allowed me to turn the car over and limp it to a safe location. I made sure to check the battery posts, and actually found out that the positive battery terminal was slightly loose and had a ton of corrosion/powder on it. I removed it, cleaned it off well, and reinstalled and tightened hard. Then I let the car sit for awhile and it actually fired back up as normal and I let it run for 15 minutes to help recharge the system. Drove the car 3 miles back home without issue (all interior lights and motor seemed strong, check engine and all warning lights turned off), but noticed by the time I got home I noticed the temp gauge was all the way at redline and the engine fan was going crazy after I had shut the car off.

I'm completely unsure whether the temp issue/loose battery terminal/car shutting off were all or partly related at this point.

Next day I went out to inspect the car. Noticed I had no warm air from the interior vents if I turned on the heater...nothing but a cool breeze. So ran a diagnostic scan and it returned a p0116: ect sensor malfunction code. Nothing else.

After doing some research online, it appeared this could also be triggered by low coolant or air in the system. I did change the coolant (genuine type 2 honda) about 2 years ago. But I do not recall bleeding the system. I also may have used a lot less coolant than I should have, especially after realizing I purchased 2 gallons of honda fluid, and still had 1 full gallon laying around in the garage.

So I checked the coolant levels and the reservoir was below the low point. Could barely see any coolant under the radiator cap. So I manually topped off/bled the system using the following steps:

- leaving the rad cap off, turned on the interior heater and continually filled the radiator while squeezing the upper and lower radiator hoses trying to get all the bubbles out.
- did this until the car was at normal operating temp (approximately 25 mins), and the temp gauge was at around 1/4 way up
- checked the interior and the hot air was back, so I thought perhaps I had scored a victory

HOWEVER, it was odd that I never once saw either of the radiator fans turn on during this time.

Went for an extended drive later that day and all seemed well and back to normal with the temp gauge never going over that quarter mark.

Fast forward a few days later to tonight.

I drive the car as usual (I'm a very light driver, never heavy footed). Approximately 20 minutes in, I notice the temp gauge once again slowly inching up towards the 1/2 mark. Oh no. Soon thereafter, it kept creeping over the half way mark and up towards the 3/4 range. Quite scary. I noticed that the temp would slowly pull back slightly below the half way mark when the car was in motion, then quickly rise when I was stopped at a light. Makes sense because cold air passing through the radiator, no? No warning or check engine lights this time around though.

Anywho, I delicately limped it back home with the temp gauge once again almost encroaching on redline. I noticed smoke seeping out of both sides of the engine bay, and a slight burning stench when I lifted the hood. Could not really tell where the smoke was coming from, but the engine fan was still going crazy after I shut off the motor just as it did the first time around.

Ok sorry for the longwinded post...but here are my questions:

1) since the code was p0116 and an ECT sensor, is it possible that the low coolant levels could be because this module was faulty/bad in the first place?
2) where exactly is this module located on the 3.0 v6? I'm guessing down on the left side of the engine block near the water pump? Is it fairly easily accessible?
I'm completely lost but thought the following might be it as it kind of resembles the shape and looks to have slight traces of coolant around where it screws in, but this on the right side of the block
under the air intake manifold



3) https://www.acuraoemparts.com/v-1999...-pump-sensor-2 lists this as part # 37870-PK2-015 ...or am I looking at the wrong thing?
are there cross compatible part numbers? Because an ebay seller lists this one as compatible with the 3.0 v6 CL and it's much cheaper but a different part number:
https://www.ebay.com/itm/262668880329?epid=2212471010

4) Is there an actual dedicated coolant air bleeder valve on our 3.0 v6 cl's? I can't seem to find any definitive answer on this, but if there is, could someone be so kind as to point me to a location or provide a pic of where it is and how to access it? I know many of the acuras of this same generation don't have a bleeder valve, so wanted to make sure.

Really hoping this is just the ect sensor and not a blown head gasket. Thanks for your potential replies!