I could not find any noticeable leaks between the manifold and the cat. I had my buddy plug the tailpipe with a baseball and there's a little pressure pushing the ball away but its really easy to hold it there.

Also I had my buddy hold the throttle cable at 2k and I used an IR gun to check the temp going in and out of the cat. Going in it was about 250F going out was like 110F so that tells me that cat is dead.

 

Alright the catalytic converter has been replaced with a straight pipe. Car sounds rude but I still feel a loss of power. I do have a RAM air intake and I read that these basically move your entire power band up into higher RPMs. I can tell when I get into the power band, there's a definite power increase after 2500 RPM, but up until that point it's just sluggish.

I didn't see any exhaust leaks between the flange in front of the cat all the way to the flange at the end of the B pipe in front of the muffler. I have an appointment tomorrow to have my exhaust system inspected for leaks.

If its not an exhaust leak, how else can I tune my car besides changing the plugs, wires, cap and rotor? I'm running out of minor parts to replace.

 

The guys at Midas spent over an hour looking over my car and could not find any exhaust leaks. They said the soot could be coming from the PCV rebreather pipe. Since I have aftermarket air intake, the pcv rebreather does not fit as snugly inside the intake pipe as it did with the stock air intake. They said occasionally, oil could be leaking out of the grommet on the air intake pipe in small amounts and then burning away slowly as it gets heated, leaving a fine black layer of soot over the entire engine compartment.

So now I'm trying to figure out why the car started to overheat that one day. I hooked a dyno dash up so I can monitor my air intake temp and this is what I've seen: Usually, the air intake is about 90F, but if I just sit in park, the temp slowly climbs, I don't know how high it will go, but I've seen it hit 120F after just a few minutes. Seems insanely hot for air intake.

So now I'm thinking that in those 20-30 minutes of idling on the freeway, the air intake got hotter and hotter because the car wasn't really moving so hardly any fresh air from OUTSIDE was coming in. I'm sure it was pumping air in there over 130F. Could this be why my car started to overheat, but then cooled back down once I started moving?

I've searched the internet far and wide for an air tight cooler box that fits around the AEM RAM air filter and connects to the 2 stock air pipes that run up from under the bumper, but have found nothing for AEM. I tried to make a makeshift box with cardboard, but I don't really think it does a damn thing.

 

Does the radiator fan work? Overheating only while sitting still is almost always because the fan didn't come on.

 

Yes the radiator fan works, I've witnessed it.
I wasn't sitting still during the overheat. I was basically moving at 5-10 mph and briefly stopping here and there for about 25 minutes.

Is there any merit to my theory or do you think it's improbable?

 

Suddenly, the rad fan is not working! I started monitoring coolant temp on the dyno dash and I noticed last night, it was getting up to 210 if I just sat there with the brake on for a few minutes.

This morning I drove it 10 miles, parked it and watched. It hit 210 again after a few minutes and the fan did not come on. It's really weird to me that on the day of the overheat, when I parked it after my commute, the fan was on, and now suddenly it doesn't come on.

Gonna jump the relay switch first to see if its that. I hope its that considering the fan itself costs 3x as much.

 

Jumped the fan relay via ECT sensor terminals and the fan came on! Going to Honda now for a new ECT sensor. Piece of crap Duralast from Autozone didn't even last a year.

 

Problem is solved. It was the ECT sensor. Now the fan comes on at 203F and shuts off at 199F.