Time for an update:
So... I've got two week+ trips to Moab under this thing and so far so good. Somewhere along the line something or somethings were fixed that straightened out the general operation which cut way back on the overheating problem.
Basically, I replaced with OEM everything under the hood except the engine cam and crank sensors, the basic wiring and injectors.
This included all the emissions stuff and the EVAP canister.
That helped a lot for last August's trip. That got it to the point where with the Contour fans on full, it wouldn't overheat on the passes or in 4WD. Unfortunately the fans were on full a LOT.
Really noisy (and irritating) when you're wheeling and both those fans running full on sucks gas. Replacing the Chinese fans with the OEM Motorcraft fans made a big difference and continue to do so.
For some reason my oil pump started leaking in Jan and it was very close to time to do the timing belt and stuff so ... New timing belt, tensioners, etc., oil pump, blaa blaa blaa. In the process the tech found out the belt tensioned was froze up. After it was fixed I realized that obviously wasn't doing anything good to the timing. We're guessing that's been that way for several years.
Short of putting a new engine in, everything Mitsu in the engine bay is now new. Yippee.
Now I'm down to no overheating in 4WD or on the highway over the passes. The highest I saw on the passes going out and coming back was around 208F and that was briefly. The secondary kicks on about there so that's what I'd expect to see. So temperatures don't look any different than my stock '03 3.5L.
I got more movement off road in 4WD but nowhere near the nightmare behavior predating last August. In general it would exhibit the same behavior as on the highway passes. The temps would slowly work their way up into the mid-200/210F range and then slowly drift back down. The fans were on full a lot less frequently this trip.
This reflects exactly what I've been seeing the last month and a half DDing around town. Usually I can get it to push up to 208-210F's kicking both fans on driving up to the house. So far it'll get up to about 203-205F or so.
Whatever was fixed - or whatever mix of things - something was wrong that was contributing to the whole overheating issue. At this point its definitely driveable and wheelable even in the 100+ temps in Moab. I have a two week Moab trip this Aug and I'll wait until then to see if I'm done dealing with this or not.
What has not been 'fixed' is the fact that there is still detonation due to the 'too much timing' issue from the 3.0L ECM. After rebuilding almost the entire vehicle in the last year and a half, I've gotten rid of so many little noises and vibrations that I can definitely hear the 'pinging' when I lug the engine a little at lower speeds. I will be surprised if I get another 100K out of the engine.
On the + side, it runs like a top. I can't complain there. Unfortunately it now sucks gas in 4WD Loanything. It is UNBELIEVABLY bad. Around 8-10 MPG. On the street its about 1.5-2 MPG less than my '03 - fairly consistent @ 15.7-16.3 MPG. I think the bad off road mileage is due to the timing but ... may be time to pull the top and do a compression check.
Edward
