Well, we got my son's truck started and seems to run fine, but finally got it road ready and took it out for a road test. Tried the 65MPH delta test and saw 20-25 degree deltas. EOT never went above 213 and ECT was around 190.

Is there a checklist of things to check? I figure to check the coolant level and whether there's oil in the coolant first thing in the morning. Would a next step be to check the coolant pressure, or drive some and see if the coolant is lower the next morning (i.e. burning off from bad head gasket)?

Do those deltas seem too high for a flush to do much good?

 

I don't see any harm in checking any of those items. However, if you want to get the delta back in line, a good flush followed by a cooler R&R looks to be the ticket. Your coolant system appears to be functioning, you're just not getting good exchange at the oil cooler.

 

The first thing to do is always to determine if the temperature values are accurate.

The first test is to get EOT and ECT at KOEO (might as well also get TFT and the IAT values) - AFTER at least 12 hours of engine-off time.

This will tell you if the sensors are within a degree or two at the low end.

Then, if you are really curious about the accuracy at the high end, swap the ECT and the EOT sensors and repeat the test to see if the results are the same.

All that said, the ECT sounds like it is accurate because of reaching and holding 190 degrees (which is approximately where a stock thermostat will hold it).

If the temps are accurate, then packagerjr has you covered.

 

Thanks, guys. I checked the sensors this morning, they were within two degrees at 91 and 93.3. But, it was prolly only 70 outside, shouldn't it be close to ambient temperature?

I forgot to mention that there are sensors missing from the air intake, on the section that clips to the back of the filter and connects to the turbo intake hose. That piece was missing from the truck and I replaced with one from a junkyard, but it doesn't have the two sensors, the filterminder and whatever the upper one is with the larger, wider connector. Would that affect the delta readings?

I'm going to swap it with the one off my truck that has all the sensors and drive it again.

I don't have a history on the coolant level yet. We spilled a bit moving the degas to get the IPR valve out and topped it up with distilled before driving, and it was a little below Min this morning, but that drive was the first time the stat has opened so I just topped it again.

I'm not seeing oil in the coolant, smoke from the exhaust, or any signs of coolant puke, and the crank evened out nicely - it no longer has the hiccup you hear in the video Eric posted. Once it started, it burped some air several times; I expect that was causing the uneven crank.

If having those sensors doesn't make a difference, the plan is to flush and then replace the oil cooler and do an EGR delete while we're in there.

 

The MAF/IAT connector? I'm surprised you can drive it if that's missing, it should set a CEL and the turbo won't spool up. Unless it's one of the (IIRC) '05s without a MAF?

 

That's the one. We're about to go drive his truck with my sensors installed.

 

My 05 with build date of 1/05 does not have the MAF the wires are there but no sensor.

 

Well, that sensor made a significant difference, but I still got a problem. We drove about 20 miles and the delta got as high as 18 degrees. Went up to 20 momentarily as we exited and decelerated to the stop sign, but most of the time, it was at 15. It was in the mid-20s most of the time without the sensor.

Would it matter that the truck has, I assume, been tuned? It has an SCT emblem on the side. Not studded and otherwise stock that I can see, except for a deleted cat.

 

Shouldn't matter if it's tuned or not.

You could try this guy's way before swapping the cooler, it would be interesting to see if his results can be duplicated:
https://www.ford-trucks.com/forums/1...il-cooler.html

 

Which part of this thought process am I confused about:

The first part of a oil cooler R&R is a basic flush with distilled water until it's clear, so I just monitor the delta during that process and see if it clears up enough to lower that delta. If so, great. Fill with coolant and live to battle another day. But that is highly unlikely, so I'd proceed to doing a "more thorough flush" if preparation for replacing the cooler. Should I backflush in such a process, if so when and how?

The answers are prolly in the tech folder document, if so, don't bother answering; I'm going to finish reading that next. Or maybe there's another link someone knows about to good info. Don't need to reinvent the wheel in this thread. I know this has been discussed a lot.