2003 2.3L getting too hot??

[Morgen01]

RonD answered my question as I read further.

 

[RonD]

When CHT gets to above 255degF computer will start cutting fuel injectors, i.e. every other one will be off, to lower the temp, engine would lose power.
So 1 and 3 would work then 2 and 4 alternating.

At 300degF all fuel is cut and, of course, engine would die

 

[Soledad]

When CHT gets to above 255degF computer will start cutting fuel injectors, i.e. every other one will be off, to lower the temp, engine would lose power.
So 1 and 3 would work then 2 and 4 alternating.

Ok, this would explain then why the truck feels like it's lost some power when I try to climb the hills after a long drive. Even the small hills it struggles on. But what's weird is that I get no MIL/CEL light and the idiot dash gauge is sitting a little above half way. It's never pegged hot.

 

[RonD]

Have you checked the vacuum on the engine.

A plugged exhaust will show up on blip test, throttle is opened quickly then closed quickly, vacuum drops but then slowly returns, not quick return, and a high rpm test, vacuum slowly drops while you maintain steady 2,500 RPM.
Plugged exhaust will cause loss of power as back pressure increases at higher RPMs.

Just a thought

 

[Soledad]

I actually did a vacuum check a few days ago. Got a solid 21.5 in.Hg. at idle. A snap check shows vacuum dropping down as expected and then coming back up quickly. And I also held it at 2500 RPM and vacuum actually went up like .5 in.Hg and never dropped. But I know that that test doesn't always tell the truth so I have a back pressure gauge on order.

What got me looking into back pressure is that I IR temp gunned the exhaust system. The pre-cat temps are about 70*-80* hotter than the post cat temps (for both cats). And for some reason there's a 150* increase in temp right at the inlet of the resonator (350*). But on the other side of the connection closer to the cat the temp is about 200*. It's weird. A jump in temp at the resonator would make me think that there's an obstruction there, but the exhaust pipe also necks down there so maybe going from a larger pipe to the smaller diameter pipe causes a jump in temps.

 

[Soledad]

Here's a list of the non-cooling system parts that have been replaced or cleaned within the
last month to two months (more of a "freshening up" than throwing parts at it to fix something):

- Air filter - Wix
- Fuel filter - Motorcraft
- Coil - Motorcraft
- spark plugs - Motorcraft
- spark plug wires - Motorcraft
- oil and filter
- PCV valve - Motorcraft
- IAT gasket (cleaned IAT) - Felpro
- Throttlebody gasket (cleaned the throttlebody) - Felpro
- Cleaned the map sensor
- Cleaned the MAF
- Found a partially leaking vacuum hose on the fuel rail damper
- Found the IMRC actuator rod was not connected to the IMRC flaps and reconnected them

I have checked fuel pressure but only at idle so far. It was about 65 psi. I just need to figure out how to rig up the tester for driving.

 

[Soledad]

This is the plan I'd like to do in the next week or two when time permits:

1. I'll ohm out the new thermostat. I think it should be anywhere between 1.2k ohm to 1.5k ohm.

2. I'll get the truck hot and test the PCM side of the thermostat connection to see if I'm getting 12v-14v. If no voltage then the PCM doesn't think the thermostat needs to be heated up. I've already checked the thermostat fuse (20a) and its good. That same fuse also provides power to the IMRC (which is working) the o2 sensors heaters and the EGR I believe.

3. While the engine is running I'll try and put 12v on the pins of the thermostat to see if it will open a little. The heater can't open it all the way but it should be able to open it a little. I just have to figure out what pins to apply 12v and ground too. If it's opening, even just a little, then that bottom radiator hose should get hot. If it does get hot then the PCM isn't opening it for what ever reason. If the hose remains cool then there's an obstruction somewhere in the system.

4. Cooling system pressure test.

5. Exhaust back pressure test.

If everything above checks out good but I still have high temps I'll buy the cooling system exhaust gas tester kit and see what it shows.
If no gasses in the cooling system then I'll do a proper flush, cleaning and fill and just run a 190* non-electric thermostat.


NOTE - I found one instance after scouring the internet of someone with a Focus who was having the same problem. The Ford dealership found that the PCM wasn't opening the thermostat. They updated his PCM with a newer strategy and that resolved the issue.

 

[pjtoledo]

The "green" was used for alot of years and pretty much the whole engine cooling system during that time was cast iron with copper radiators/heaters with rubber hoses and a few steel parts like water pump impellers and thermostats.

As manufacturers started using different metals, like aluminum, the chances for galvanic corrosion increased, but as long as coolant was changed every 2 years protection remained, except not every one does that, and on older engines that wasn't a big issue since metals were the same, with different metals it was a problem.

OAT was developed for longer term protection, 5 years, so problems would occur AFTER warranty period, my own opinion , if people didn't change coolant when required.

There are all kinds of tests done as to which is better, IAT, OAT, HOAT, ect......., and with which engine models, years and displacement.

I can't say which is better scientifically on paper, but others have done that so I don't need to
On vehicle less than 10 years old I tend to go with what manufacturer spec'd for that year and engine.
After that I figure I am going to get leaks, lol, and go with my more practical plan short term protection, not figuring I will get that 5 years at this point, lol.

'ya got my head spinning on all the different types of coolant.
since my 05 2.3 has some temp issues, and 300,700 miles on the original coolant, I'm about ready to replace the coolant.
is the Peak long life concentrate ok by you?
it says "all makes, all models" on the specs but does not reference the Ford spec of WSS-M97B51-A1 factory fill was Premium Gold, yellow color.

this thread has been quite informative as my 2.3 has never given me any trouble, so I had no reason to look into the de-gas and special thermostat.

Perry

 

[Soledad]

Coolant   0 psi  4 psi  8 psi  12 psi   16 psi  20 psi   24 psi
--------  -----  -----  -----  ------   ------- -------  -------
Water     212F   225F   233F   242F     252F    260F     265F
33%       220F   230F   240F   253F     260F    268F     273F
44%       224F   234F   245F   257F     265F    272F     279F
60%       231F   241F   253F   264F     273F    280F     285F
50%       226F   236F   248F   259F     267F    275F     280F

I thought this was kind of cool. The boiling point of coolant mixtures at certain pressures. (@ sea level)

The degas cap on these systems is rated up to 16psi. Anything more than that and I think it starts puking. I'm not sure what the psi of a properly functioning system is but I would bet it's somewhere between 2 psi to 8 psi.

 

[RonD]

Yes, that is the anti-freeze/anti-boil properties from the ethylene glycol(or propylene glycol) added to coolant.

The pressure component is from bubble formation in a heated liquid, boiling is of course when bubbles form, and that is directly related to the pressure on the liquid.
i.e. water boils at 212degF near sea level air pressure and at 200degF at 5,000ft elevation air pressure, less pressure allows bubbles to form at lower temp.
And once a fluid starts to boil it releases heat so doesn't get hotter, just turns into a vapor.

So more pressure..........read pressure cooker, lol, cooks food faster because temp can get hotter with the higher pressure inside the cooker.

 

[Soledad]

Something came to mind when I was talking to my buddy about this problem.

When I installed the radiator, the top radiator hose inlet had a large red cap over it for protection. However the bottom outlet did not. I never checked to see if maybe the factory had shoved some paper or packing foam or something inside of it to keep junk from getting in it. I just "assumed" it was open.

When I've got some time I'll drain the system and check that outlet on the radiator, the bottom hose and inside the thermostat to see if they got jammed up with FOD. I'm really hoping that's the issue.

 

[RonD]

Long shot but not a "no shot"

I would also remove lower rad hose completely, if there was something in there it may have been push up to water pump end of hose

 

[Soledad]

Ron, yeah, I'll be removing all of the hoses and checking everything next week. Gonna pull out the thermostat too and see if I can bore cope the coolant path/channel. Actually, I'll see just how much of the cooling system I can get into with my bore scope.

I had about an hour today and tested the thermostat and wiring.

- The thermostat heater read 15.4 ohms across both pins so that's good.

- The light blue/orange wire had 14.2v on it at KOEO and KOER which is good. That comes from fuse 41 under the hood.

- The dark blue wire had 14.2v on it when the engine was cold. When the engine is hot the voltage on that wire should drop way down. It's the wire the PCM uses to duty cycle the heater in the thermostat. A variable ground. With the ECT @ 228* and the CHT @ 255* the voltage remained at 14.2v. After 30 minutes of making the engine hot the voltage on that wire never dropped. I used my non-contact temp gun and the thermostat body was reading 152* and the bottom radiator hose was reading 125*. And the bottom radiator hose definitely had pressure in it.

From this I figure we have a few things:
1. The various sensors are telling the PCM that things are alright, the coolant temps are fine and there's no need to turn on the heater in the thermostat.
2. There is an open somewhere between the PCM and the thermostat.
3. The PCM isn't providing ground.
4. There is a blockage in the cooling system (that's still on my list of things to check).
5. I've actually got a bad thermostat that won't open at all.
6. The cooling system is just fine and it's working normally.

As a test in the next day or two I'm going to heat up the engine good and hot, disconnect the wires from the thermostat, put 12v on the thermostat pin that connects to the light blue/orange wire and ground the pin on the thermo that connects to the dark blue wire. And then see if the coolant temps change. It won't open the thermostat but it will drop the opening temp by about 50*.

 

[RonD]

Look at the water pump impeller blades, they can get eaten away by electrolysis.

 

[Soledad]

RonD,

I actually replaced the water pump about a week or two ago.

Here's all the parts that have been replaced within the last month or two as part of either a complete failure of the original part or just a freshening up of the old parts that have a lot of mileage on them:

- Degas bottle
- Degas bottle cap
- Radiator
- Radiator hoses
- Thermostat
- Waterpump
- PCV valve
- Spark plugs
- Coil
- Fan clutch
- Air filter
- Fuel filter
- Vacuum hose between intake and fuel rail pressure damper

I've also cleaned the IAC, MAF, MAP, throttlebody and replaced the gaskets on the IAC and throttlebody.