Duratec cooling mods -- Need to clear CEL - Page 4

tomw0 · #46 05-07-2016, 04:47 AM

I think that the automatic door lock feature might feed VSS to the GEM or SJB.

I wonder if turning that feature off might have an effect.

Would it be possible to wire in a remote potentiometer(variable resistor) to the thermostat and change the resistance so the computer is fooled about temperature?
tom

Soledad · #47 05-07-2016, 08:02 AM

tomw0,

I've been thinking about this and I don't think the PCM/ECU monitors the resistance of the heater in the thermostat other than it is there or not there. I think it works solely on the CHT/ECT temps and duty cycles the dark blue wire (a switching ground??) on the thermostat depending on those temps to open up the thermostat a bit earlier in it's temp range.

In my case, I never so the dark blue wire switch even when temps "seemed" to be above normal while at idle. But, I never drove the truck to see if it will actually duty cycle when temps get even higher. I don't think I could rig up something safely to monitor that while I drive. While it was idling I just back probed the harness side connector with paperclips and alligator clips. It wasn't pretty.

It's funny that even after a hard drive with CHT temps in the 260's the thermostat body only reads around 170*. If that is the true temp of the thermostat then it's got another 30* before it even starts to think about opening.

----------

By the way, here is the OEM coolant flow map and one I created from a cooling system parts diagram. There's a lot of bypassing or maybe it's re-circulation going on if I'm looking at these properly.

riscorpian · #48 05-07-2016, 09:55 AM

Those diagrams really do mirror another one of my bigger annoyances with this engine: why the hell is the coolant tank on the passenger side of the engine bay? It would've been far easier to design it so that it's on the driver's side. Or even better, how come this engine is oriented with the intake on the driver's side? Just about every other FWD motor I've seen has the exhaust side in the front. Thus, when it's mounted longitudinally (in a RWD application), the exhaust would wind up on the driver's side. The Duratec 2.0/2.3 have the intake up front in FWD vehicles. I guess it's pretty trivial in that case, but it really starts to cause issues when adapted to RWD.

On a similar note, check out the alternator position. The battery is on the opposite side. That's two systems in a row that have to stretch across the engine bay to reach all of their components. What good does all of this do? I suppose the larger amount of hose increases the cooling system's capacity, but that also makes it a royal pain to bleed properly. Plus, this engine doesn't even need that! It heats up pretty fast with the thermostat closed, but it's insanely efficient at keeping itself cool otherwise. The stock system is waaaaay overkill here. Unfortunately, the poorly-implemented electronic thermostat and uncomfortable amount of plastic in the system overshadow that fact so much that you'd never know.

Anyway, as for the controls, I might be able to do some monitoring. If I can figure out exactly what the signal is that's being sent, then maybe I can work out how it's controlling it and what it does in reaction to different conditions. My SCT software also claims to have Output State Control functionality on Ford vehicles now, so there may be a way I can manually override something. It's worth a shot, I guess.

GFS, do you still have your old electronic thermostat? I'd like a better look at the electronics inside, if possible. Shouldn't be too terribly hard to reverse engineer.

GSF1200S · #49 05-07-2016, 08:16 PM

Quote:

Originally Posted by tomw0

I think that the automatic door lock feature might feed VSS to the GEM or SJB.

I wonder if turning that feature off might have an effect.

Would it be possible to wire in a remote potentiometer(variable resistor) to the thermostat and change the resistance so the computer is fooled about temperature?
tom

Good to know on the first part. That may be why ours has a code- I dont have power door locks and so perhaps there is no input to the GEM?

Like Soledad I dont think the computer considers at all the resistance in the heater circuit. Im not even sure what the point would be- the computer must consider what the engine temp is in order to determine fueling and timing- the resistance of the thermistor in the thermostat would only tell the computer what it already knows from its maps, the CHT and the ECT sensors, and the knock sensor. I could be wrong though- just my thoughts on it.

Quote:

Originally Posted by riscorpian

Those diagrams really do mirror another one of my bigger annoyances with this engine: why the hell is the coolant tank on the passenger side of the engine bay? It would've been far easier to design it so that it's on the driver's side. Or even better, how come this engine is oriented with the intake on the driver's side? Just about every other FWD motor I've seen has the exhaust side in the front. Thus, when it's mounted longitudinally (in a RWD application), the exhaust would wind up on the driver's side. The Duratec 2.0/2.3 have the intake up front in FWD vehicles. I guess it's pretty trivial in that case, but it really starts to cause issues when adapted to RWD.

On a similar note, check out the alternator position. The battery is on the opposite side. That's two systems in a row that have to stretch across the engine bay to reach all of their components. What good does all of this do? I suppose the larger amount of hose increases the cooling system's capacity, but that also makes it a royal pain to bleed properly. Plus, this engine doesn't even need that! It heats up pretty fast with the thermostat closed, but it's insanely efficient at keeping itself cool otherwise. The stock system is waaaaay overkill here. Unfortunately, the poorly-implemented electronic thermostat and uncomfortable amount of plastic in the system overshadow that fact so much that you'd never know.

Anyway, as for the controls, I might be able to do some monitoring. If I can figure out exactly what the signal is that's being sent, then maybe I can work out how it's controlling it and what it does in reaction to different conditions. My SCT software also claims to have Output State Control functionality on Ford vehicles now, so there may be a way I can manually override something. It's worth a shot, I guess.

GFS, do you still have your old electronic thermostat? I'd like a better look at the electronics inside, if possible. Shouldn't be too terribly hard to reverse engineer.

I think the answer is that its a cheap truck. The truck had already been designed to have the battery on the drivers side, the coolant and windshield washer tank on the passengers side, the abs module on the drivers side, etc. So, whats cheaper: a) moving the battery, coolant tanks, windshield washer bottle, and possibly abs module, or b) creating a cheap hose that runs around the back of the motor. I think the answer is b. What I dont get is, why not run the coolant lines for the degas across the front of the truck- it would be much easier to change and require less hose. Maybe its because they wanted to charge more money for labor when it failed, idk.

In terms of your idea, i dont know how you would pull it off. The biggest issue is that the pcm itself doesnt supply any current when the truck is cruising, so youd still be stuck with the temp up in the 260/270s range while cruising. Youd also get all the expansion/contraction from the heat cycles as the electric thermostat did its thing. Youd almost have to generate current with something to bring the cruising temp down, but were almost approaching "whats the point?" considering the 2006 thermostat mod is available for cheap. Am I missing what youre going for here?

I do still have the old thermostat and I have no issue taking it apart, though it may be a couple days.

riscorpian · #50 05-07-2016, 10:11 PM

Quote:

Originally Posted by GSF1200S

Good to know on the first part. That may be why ours has a code- I dont have power door locks and so perhaps there is no input to the GEM?

I have no power door locks either. Or power windows. Or power mirrors (that one REALLY annoys me though, so I might mod that). The GEM seems to really live up to the GENERIC part of its name, so it's probably not very smart. The code might just be the scanner picking up the GEM's own confusion over something totally benign. Interesting, maybe, but not really useful for anything.

Quote:

Originally Posted by GSF1200S

I think the answer is that its a cheap truck.

No thinking required there. That is the answer. Ford built the Ranger chasis to be generic enough to accept a range of different motors. The Duratec engine just happened to be weird and different enough that it clashed with the existing layout way more than usual. My point is that it just emphasizes that this motor was not designed for a truck at all. It doesn't even fit properly in an engine bay that's been kept pretty constant for decades. They were able to make it work, but it did cause some oddities in the design.

Note how a lot of the systems that are driving all of us insane were removed or significantly improved just a few years after they were introduced. That just goes to show that Ford didn't like them any more than we did. We just need to prepare a decent list of swear words and throw toolboxes at it until it stops not working. Ford had to invest loads of money in R&D and proper testing before they could modify it enough to get rid of that stuff. I've long held the opinion that some of these systems were designed this way to overcome some kind of obscure problem when there wasn't enough time or money to find a proper, cleaner fix. With time, it did start to get better. Kind of leaves us out in the cold with our fundamentally flawed older engines, but at least Ford was committed to making it work in the end.

Quote:

Originally Posted by GSF1200S

In terms of your idea, i dont know how you would pull it off. The biggest issue is that the pcm itself doesnt supply any current when the truck is cruising, so youd still be stuck with the temp up in the 260/270s range while cruising. Youd also get all the expansion/contraction from the heat cycles as the electric thermostat did its thing. Youd almost have to generate current with something to bring the cruising temp down, but were almost approaching "whats the point?" considering the 2006 thermostat mod is available for cheap. Am I missing what youre going for here?

The point is that I want to see if this system ever had a chance in the first place. My belief is that Ford removed the system since it was so flawed that getting rid of it was cheaper than trying to fix it. But if they had opted to fix it, how would it perform and what benefits would it produce? That's what I'm curious to see.

Quote:

Originally Posted by GSF1200S

I do still have the old thermostat and I have no issue taking it apart, though it may be a couple days.

Good to know. I have no clue what info I need yet though. My circuitry knowledge is still developing, so it may take some more experimentation on my end before anything else.

tomw0 · #51 05-08-2016, 07:45 AM

But if they had opted to fix it, how would it perform and what benefits would it produce?

Did the same thermostat system work in the FWD models? My first take is that it was designed to keep the engine temperature as close as possible to the detonation/pinging point to maximize fuel economy. Every extra tenth of a mile makes a difference in CAFE fuel numbers averaged over the fleet sold aggregate 'number'. If they can wheedle a bit here and there it can add up to more profitable sales of other models.
The Ranger was the 'red-headed step child', a phrase I learned from Sutherners, meaning it didn't quite belong (nobody had red hair in the 'parentage'...??). It was not invested in as they 'knew' it was going away, and it would 'cannibalize' F150 sales.
IMO, that was b.s., as I am not in the market for a truck that I can't see into the bed nor fit in my garage, which gets 20-22mpg on a GOOD day(no matter their official numbers), where I can pull over 25mpg without even trying, better on the highway.
They band-aided it to fit, and sort of 'rotated' it in their CAD design software(I bet) and saw what things needed to be 'stretched' to make it work 90 CCW viewed from above.
Most FWD have an electric radiator fan that kicks in for A/C operation, but likely doesn't do a thing going down the highway. Do these have an electric only or a 'combo'? From the image above, there seems to be a normal 7-blade as used on older models. It might be that the electronic thermostat may be integrated to the fan controller, so it can respond quicker, where the minimal coolant liquid capacity(save weight.. more mpg) has to be circulated and COOLED RIGHT NOW as there is no 'excess' COLD(relative) coolant floating around in the radiator that can be 'freed up and allowed to flow' to take away the heat caused by hard work. IOW, there is marginal coolant capacity, and the sum effect is that the system is easier to get hot, quickly, and will not remove heat, as quickly. Or not...
tom

riscorpian · #52 05-08-2016, 08:28 AM

My understanding here is that the engine is so efficient that it can't heat itself up fast enough unless that thermostat is sealed shut. But since a mechanical thermostat doesn't open immediately, they need to compensate by lowering the open temperature, which leaves a gap between the thermostat opening and the ideal operating temperature. And since the engine cools itself too well when opened up to the full cooling system, it's going to just take that much longer to finish warming up. Furthermore, it can cool itself back down so fast that it risks dropping below the sweet spot temperature, and then taking too long to get back there.

Thus the electronic thermostat makes sense. With an electric assist, it can be allowed to push that limit even closer. But the implementation didn't work well enough. There's still a delay with the electronic opening, defeating the purpose. And yet, since they designed everything around that idea, it ended up hurting big time. Now everything gets too hot faster, and the thermostat pops way open to cool it back down even faster. That just adds to the temperature delta of the heat cycles it goes through after the initial open. It's probably also the reason why they opted to use so much plastic. "Hey, we have an electronic system that should keep the temperature more stable. We can get away with using cheaper plastic!" The '04 revision still has a lot of plastic, but it seems to hold up a lot better.

It's a stretch of an idea, but there is logic in there. Ford's implementation never worked, but that doesn't mean the concept itself is impossible. I have an engine driven by a computer that's already programmed for the ideal conditions, so I want to see if it can be taken advantage of. The mechanical thermostat mod certainly helps, but I don't know if it fixes the high temperature delta after warm-up. And if the electronic assist was quick enough, could that be enough to prevent it?

As for the fan, all models with A/C have an electric fan in front of the mechanical. I don't think the older Limas had one on non-A/C models, but I'm not sure about the '01+ Duratecs. Given the power of this cooling system, a lot of people have just opted to remove the mechanical fan. I tried that for a while, but the next summer was just brutal. With the fan back on and a new thermostat, it's way better.

tomw0 · #53 05-09-2016, 04:37 AM

Taking the idea above a step further.

If the computer KNOWS it is feeding a lot of fuel, the throttle position senses a lot of throttle, and the temp is 'close', maybe turning on the heater would be a good idea in a few seconds(variable based on ???) as we expect a temp spike.
A second thing would be to limit the cooling of the radiator. Maybe don't need such a surface area & volume, thus removing some 'inertia' or 'hysteresis' from the calculations. Less coolant == quicker response to delta T. OTOH, small radiator will be limited in BTU/h heat rejection. Wotta mess you've gotten us into, Ollie...
tom

Soledad · #54 05-10-2016, 03:15 PM

UPDATE:

Success!! Just got back from a 5 mile test drive and the truck is running 204*-208* ECT and 210*-214* CHT. I'll take it on a 30 mile test drive tomorrow when I make a dump run. I really hope this is the end of the engine running too hot issue so I can move on to fixing other things.

Here's what I did:

A few days ago I replaced the CHT sensor and connector. I noticed in FORScan that before the replacement my cold soak temps were IAT @ 64*, ECT @ 68* and CHT @ 68*. After the CHT replacement the cold soak temps were IAT @ 68*, ECT @ 64* and CHT @ 64*.

Today I drained the cooling system and tested flow through the radiator and block (with thermostat removed). Both had absolutely no blockages. Water was coming out at full volume.

I also replaced the steel tube that connects to the top radiator hose, heater core and degas bottle. Mine was coated inside with rust and looked horrible. I then replaced the electronic thermostat with a 190* non-electric Motorcraft thermostat. But, I left the old one connected to the wiring just so I wouldn't get a CEL. I'll install a resistor soon. Not sure if I should go with a 15 ohm 1 watt resistor or 1500 ohm 1/2 watt resistor. The thermostat heater measures 15.4 ohms.

Any way, and the pièce de résistance, the original owner must have had someone install a Dorman brand "Tee" when the original "Tee" above the starter cracked. Well, that Dorman Tee was soft due to the heat and cheap plastic used during manufacturing and the hose clamp was crushing it reducing the size. I replaced it with a Sharkbite UC417LF brass tee. It was a smidgen smaller than the hose size but the hoses clamped down just fine........so far. Hopefully this Sharkbite tee will work until I can get enough motivation to replace the whole hose assembly. Yuck.

NOTE - just for future searches, pulling out that steel coolant tube was a real pain. But, I finally got smart. I used a ratchet strap hooked on to the heater core connection tube and the radiator support area and just ratcheted it off. It was easy peasy doing it that way.

EDIT: Did a dump run today (about 25'ish miles round trip) and ECT stayed around 208*-212* and CHT fluctuated between 238*-245* using Torque Pro to monitor temps. I'd call that a success.

Soledad · #55 05-11-2016, 01:08 PM

Quick question; Why was a 1500 ohm resistor used instead of a 15 ohm resistor? The heater circuit in the thermostat measures 15.4 ohms on my MM.

My last electronics class was back in A-school in 1989 so I've forgotten everything.

riscorpian · #56 05-12-2016, 11:12 AM

In my case, I just happened to have a load resistor from a set of LED turn signals I'd purchased a while back. Since I did the actual proper hyperflash fix of installing an electronic flasher relay, I didn't need them. But they came as a kit, so I just had them anyway. Since the thermostat circuit seems pretty stupid, it doesn't really need anything specific to fool it. Just something that maybe possibly looks like there's some kind of load at all should be enough. So whatever is on hand should be fine.

*EDIT: Whenever I get enough time to play with the wiring, I'll reroute it to the cab so I can watch it with an oscilloscope while it's running. Should be better for actually seeing it in action.

Soledad · #57 05-12-2016, 11:51 AM

Quote:

Originally Posted by riscorpian

*EDIT: Whenever I get enough time to play with the wiring, I'll reroute it to the cab so I can watch it with an oscilloscope while it's running. Should be better for actually seeing it in action.

Cool! Thanks for the info. I do want to use a resistor that has a decent heat sink on it just so I can mount it like how it might have been done if it were OEM.

Oh, and I'd love to see this thing on an o-scope while the truck is moving down the road and up to temp and under heavy load. I have a feeling that the resistive circuit in the thermostat probably isn't called into action very much due to how well this engine and cooling system seems to "cool".

GSF1200S · #58 05-12-2016, 02:15 PM

Quote:

Originally Posted by Soledad

Quick question; Why was a 1500 ohm resistor used instead of a 15 ohm resistor? The heater circuit in the thermostat measures 15.4 ohms on my MM.

My last electronics class was back in A-school in 1989 so I've forgotten everything.

Because I found another guy somewhere on the interwebz who verbally demonstrated a command of knowing how this system worked, and he used a 1200 ohm 1/4 watt resistor without issue. Since I didnt have resistors laying around like riscorpian I went to Radio Shack and looked for the closest resistor to 1200 ohm 1/4 watt I could find, and 1500ohm 1/2 watt was it.

I really dont think it will matter. Ive done a trip from Texas to Florida and back with that resistor as well as plenty of miles locally- never a CEL and my truck hasnt burned to the ground.

The computer doesnt change the fueling/spark/etc based on this value. As long as the resistance falls inline with its idea of working, it will go on thinking the heater circuit is working and will ATTEMPT to control the engines temperature (which wont work as the thermostat is fixed) while fueling/sparking the engine in accordance with values retrieved from the CHT/MAP/Knock/MAF sensors.

Keep in mind, voltage is the desire of electricity to travel, amperage is amount of electricity moving, and ohmage is the resistance in a circuit to the flow of electricity. The higher the ohm load of a resistor, the less current flows through that circuit given a fixed amount of voltage. Ever been shocked by a distributor coil or coil pack? Youve been hit with 10000+vdc then! It doesnt harm you (but will sure piss you off) because there is such little amperage. The high voltage makes what little current is there jump a very large gap (or push through the resistance of a human body) to get where it wants to go (ground).

By using a 1500ohm resistor instead of 15 ohm, the circuit flows much less and thus doesnt require as much substance from the resistor (or doesnt flow as much BECAUSE of the lesser substance of the resistor). Its actually more complicated than all this, but you get the idea.

Either one will be fine- use whatever youre comfortable with. I have myself thought of switching to a resistor with a heatsink just so I can mount it more properly than how it is now.

Soledad · #59 05-13-2016, 11:11 AM

Ok, thanks for all the help on this. I just ordered up a 1.5k ohm chassis mount resistor. I think I'm going to dremel off the male connector on the thermostat and try and make this plug-n-play. That way, should I ever get rid of the truck, the next owner can put an original thermostat back on it and the connector/harness won't be all hacked up.

NewShockerGuy · #60 11-17-2017, 08:48 PM

Glad I found this thread because I'm so annoyed.

I have read everything here. Everytime I drive my truck I smell coolant. I checked and sure enough the top of the under side of the hood cover has been misted by coolant from the degauss rad cap. (I have a 2001 2.3L).

Af first I thought it was the cap so I purchased a new OEM motorcraft one. Still had the same problem. Figured it was the degauss bottle. Bought an OEM Ford and replaced it and then also replaced the cap again for OEM.

I can still see faint traces of where coolant is coming out from the bottom of the cap. Back in 2013 I replaced the thermostat that was original on the truck for an OEM Motorcraft one:

https://www.amazon.com/gp/product/B0...?ie=UTF8&psc=1

That exactly, which is rated at 190'F.

I have an ultragauge so I can see the engine temp. It ranges from about 190'F to about 215' F. IS this normal? I don't know if that's using the top engine sensor by the spark plugs. That too has been replaced with new many years ago. For whatever reason my old sensor was reading something like 265'F and as soon as I replaced the sensor it read normal readings...etc.

I will note that I fill the coolant bottle to MAX... after reading perhaps that's too much and I should just slightly keep it at above MIN?

There is no other leaks other than where the cap is... I don't believe there is any blockage at all because when I turn on my heater that works perfectly fine and is hot. When the truck is running and I open the hood I can see the top most coolant hose spitting coolant back into the degauss bottle which I am assuming it's circulating as it should. Nothing is boiling. No coolant in the oil either...etc.

See pictures of my drive today going to work. About 35 minutes of highway driving 65mph. Engine temp reads in order from: 199 to 215'F. Is this normal? Shouldn't that read at 190'F because of the thermostat opening at 190'F? Or is it going to be hotter because well... it's the engine?

This is the only thread I could find that remotely covered anything about this.

Thanks,
-Nigel