The fan clutch is temperature controlled. In AZ it's hot so it's going to be engaged all the time? Maybe go for a drive late at night when temperatures are lower.
New OEM fan clutch but still roaring dump truck? (2 Viewers)
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Thanks. I have the same problem in the winter when OAT is around 60-70. Just takes longer for the fan clutch to engage. But once engaged, it doesn't seem to disengage during driving, until having been parked for a while. Are there any other members who live in AZ perhaps who can chime in on whether their trucks always sound like a roaring airplane or dump truck with the whirling sound?
Some vehicles have electronic control of the fan clutch (like my F-350). Ours does not, so the coolant temp sensor doesn’t matter.
I also believe, and others have confirmed similar data, that low 200s on coolant temp is normal in our hot climates. It’s 105 in north Texas at the moment, and I expect to see 203 on my drive home. I’ve cleaned the radiator and have replaced everything in the last three years. As the temps come down, my cruising temp goes down to high 180s in the winter.
I also believe, and others have confirmed similar data, that low 200s on coolant temp is normal in our hot climates. It’s 105 in north Texas at the moment, and I expect to see 203 on my drive home. I’ve cleaned the radiator and have replaced everything in the last three years. As the temps come down, my cruising temp goes down to high 180s in the winter.
Did you inspect and wash radiator fins, and with skid plate off. How was it?
The ECT temp sensor has very little to do with fluid (fan) clutch. Other than, the ECU uses data from it as it does from other sensors, to determine fuel trims, etc. Which if running lean (LT FT above 5%), we run a bit hot.
Fluid (fan) clutch engagement is based on heat. The coil visible at front of fluid clutch expands with heat, turning a center shaft it connects to. The center shaft opens and closes a valve within fluid clutch, resulting in varying resistance applied to fan. Fan clutch should still engage and disengage to varying degrees even in higher OAT conditions. Since higher OAT & ECT result in hotter air passes out back side of radiator fins, on to FC's coil. It's understandable, the higher the OAT the sooner fan engages to a greater resistance. But as you noted, it is not fully engaged shortly after cold start.
Bottom line. Based some of your statement, and on ECT's you reported. Fan clutch is working as it should. But it does seem to me, your ECT are a bit high. Especial when cruising "driving around coolant 199-206F" even with OAT of 109f. But my tests were at OAT's of 100F full sun 1-3PM. Would 9F (109F) make that much difference while driving? Seems you should still see 194 to 197F, while move 35 MPH or more!
Very unlikely, two new OEM fluid clutches bad out of the box. The biggest complain of new FC is: Not enough resistance. Which some replace FC oil with a thicker oil, to increase resistance increasing cooling.
12 MPG near sea level in a built rig, seems almost to good. This could indicate running lean (higher cylinder temps).
Note: ECT data from temp sensor, limits transmission up shifting while engine cold. Which may result in higher engine RPMs, depending on drivers input (gas pedal) while driving a cold engine. The ECT range you reported did not indicate a sensor issue but does not rule it out either.
I do not recall you talking much about actually testing of fluid clutch!
How I test fluid clutch (06-07) 2UZ-fe VVT):
- Cold engine/coolant/radiator, before start-up. Hand spin fan blades will have mild resistance to spin at first. After spinning a few revolutions, resistance lessens. If fan will not spin (locked), fluid clutch is bad.
- Cold start engine: RPMs will be high, SAI pump on (can be heard), engine cooling fan roars and cannot be stopped from spinning.
- About 30 to 90 seconds after cold start, fluid clutch resistance reduces (disengages). At 90 second the SAI pump (blower) shut down (sound like turbine shutting down) and RPM are dropping back ~1,200 to 1,000. Fan blades can easily be stopped with either a rolled-up paper or water pressure.
- As ECT climbs above normal operating temp and radiator radiates more heat, as works to dissipate coolant heat. The radiant heat, heats coil on fan clutch expanding it turning fluid clutch valve. Fan cannot easily be stopped from spinning with water pressure or rolled up paper.
- Stop hot engine while fluid clutch engaged. Very high resistance felt, when spinning fan by hand.
A stuck fluid clutch will result in lower ECT and lower MPG. They'll typically also result in fan blades/fluid clutch, being off balance. Resulting in excessive engine vibration.
I had A typo earlier. I DO NOT drive in OAT of 107-109F, typically here in Colorado. My test of ECT have been at 100F, 3 PM fully sun hot asphalt, AC frt & rear max, stop and go traffic after 300 miles drives up and down high altitude passes. I only touch on ECT of 200F 2006-07 (98-02 ECT 190F) for a moment and while at a stop, during stop and go traffic on hot black top.
You're driving around reading ECT of 199-206F with OAT 107-109F, seems high to me. But again, I've not logged ECT above OAT of 100F.
I notice you use one of those special funnels to fill radiator.
Have you checked coolant level under the cap. Before starting up, before sun comes up and after 8 hour cool down?
This is best done, with front of vehicle higher than rear, so high point (air pocket) is at rad neck/cap. Any air under rad cap, coolant system will not function at peak.
Additionally, I'd check to make sure reservoir full and its hoses & cap clear of obstruction and inner hose drops straight to bottom of reservoir. I find many reservoir hoses curled up, from getting hung on shelf inside. This result in sucking air, into radiator (air bubble). I also find, clog in reservoir hose or its cap and or bad radiator caps. All must work as designed, or you'll run hot.
Your reported transmission, lack of power and RPMs not wanting to go over 2,200 at times. Are indicating some other issue(s). Running logs of: A/T temp, Fuel trims, ECT, RPM, MPH & IAT. From cold start-up through warm up and while the issue you've reported are happening, may yield clues.
Although the symptoms you've mentioned, don't point to typically 06-07 bad fuel pump. Slowed fuel delivery from clogged fuel sock & filter, result in fuel delivery issues (reduce fuel flow and or pressure). We'll run lean (hot) or even result in some issues you've mentioned. We want to see long-term terms of 0%, but 3% are fine, we do not want above 5% while cruising steady on flat stretch of road.
I'll also note, you've a built rig. Large tires & extra weight take more energy/HP to move down the road. So you'd be running engine harder than I did during my ECT testing/logging, which were in stock configuration. The large iron bumpers & winches also retain more heat. The OAT sensor (just behind bump on RH side) is affected, in that it takes more time to get to actual OAT at sensor. Sun, rain even washing greatly change the temperature of these iron bumpers. This also affects IAT, read at MAF. So parked in sun will have long lasting effects, than we see on our stock plastic bumper. keep in mind. The ECU uses all sensory input.
I'm interested in hearing about data logs while driving, testing FC and cleaning radiator fins.
Fuel trims do not show the engine is running lean. In fact they show the opposite, the ECU is adjusting the fuel mixture to prevent it being lean.
AFR is the only way to know the engine is running lean and it will throw a CEL if so.
AFR is the only way to know the engine is running lean and it will throw a CEL if so.
Long term fuel trims are showing "what" ECU is doing, to correct fuel trim to achieve a 15:1 AFR. A positive LTFT, is indicating a lean running condition. When we see LTFT above 5%, we need to look at why we're running lean. Easy way to say/reads this is; needing more than 5% increase fuel to the mixture to achieve 15:1. We also compare LTFT to STFT, to see if ECU adequately correcting. Wherein most cases the ECU will correct FT enough to prevent, cylinder head temp being to high (lean) or low (rich). The FT is an indicator very helpfully to watch, as a clue something is not operating optimally.
A case I just corrected fuel trims on (lean running). Was 06LC w/250K miles, with LTFT ~7%, NO CEL or pending DTC.
After using 44K a few times, full tune-up (plugs & boots, vacuumed lines, PCV, TB CLN, T-belt, etc.), coolant service and all fluids over last few years of servicing. This excellent running, handling, braking, shifting LC. A/F and o2 sensors checked out fine, with no indication of weak MAF or damaged CATs. Compression good.
But LTFT remained over 7%, the entire time. Last month, getting it ready for a very long trip and move out of state. We R&R fuel pump & filter. LTFT for the first time came inline afterwards. LTFT now steady at 0-3%.
It was interesting what I found in fuel tank, fuel pump sock and fuel filter before replacing.
Which must have been restricting fuel flow (lean condition) indicated by LTFT 5-7%, now at 0-3%.
Iron, remains of Rust from fuel station storage tank sediment.
Perhaps we're on same page, just not communicating well!
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Just for the sake of accuracy the 2UZ targets 14.4:1 to 14:7 AFR depending on engine temperature, load, and other factors not 15:1. 15:1 would be a lean condition and would throw a CEL.
