My red hx is worn out as well. It's getting 32mpg city, I've never gotten that low in an HX ever. My black car will get 38mpg without sleenizing but it's a low mileage car
I'm not even going to bother with compression testing my red car, probably going to be low too. one thing I am going to change however is the catalytic converter. I'm not getting a check engine light however it has a gas stench out of the tail pipe.
I mention that because I can tell you re used the old factory 300k mile catalytic converter. New cats are 2 pieces compared to the factory one piece
Cheers
The clear cam cover holds up pretty well over time. It gets a little dirty after a while but no yellowing or anything
My red car is at 242k miles and has a very noticeable lack of power compared to my 159k mile black hx, which should not be the case since I have tons of new parts on my red car. Which leads me back to the poor performance of the red car.
Red is actually a California spec ecu, black is federal. Putting in a federal ecu did not increase lean burn in red, or gain any gas mileage, and the car still can't maintain lean burn.
The most likely causes for reds problems:
Clogged egr port on cylinder head disrupting egr flow, or filthy intake manifold
Poor catalyst effeciency disrupting primary oxygen sensor readings