I have seen this already:

https://www.fitfreak.net/forums/1st-...honda-fit.html

But my situation is a little different, I can't shift manually using the paddle shifters, but I can definitely go higher than 3rd gear, I can even rev it up and down as normal, but in cruise it doesn't control the gears any more.


This happens on each of my road trips that I do once a year, the first few times, it would occur in the California mountains that would cause me to drive in 3rd gear at 60~70 mph for very long periods of time (20 ~ 40 minutes at a time). This is kind of expected, this last year, I've upgraded and tossed a 12x8" transmission cooler and bypassed the main radiator to make sure I can get more time out of it. Now I can drive in 4th gear at a reasonable 70~80mph for about 2 hours at a time, but after 2 hours, I get the D flashing, and P0718 on the OBD2 scanner.

The transmission cooler is not unbearably hot, but it's hot enough to know it's working. I open the engine bay hood and it's extremely hot with both my radiator fans blowing hard. I'm assuming the P0718 is due to the sensors overheating and not providing speed data to the ECU.


Now my question, how can I get some more air into the engine bay, or provide better cooling to my engine? Going 45mph is not acceptable and would like to get some more endurance out of my car.


TL;DR, please help me cool my engine some more, so that I can endure high speeds at lower gears for longer periods of time, I already have a tranny cooler.

 

what do u mean by bypassing your main radiator?

 

https://www.fitfreak.net/forums/fit-...kevin1107.html


I bypassed the radiator, and went to the tranny cooler directly.

So, no ideas on how to cool the engine off some more?

 

Should I give up trying to get more out of the engine, and give it a break every 4~8 hours on a 24~36 hour driving session?

I was forced to take naps to cool off the engine, that sucks.