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2004 pcv?


modelageek

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Can someone explain my pcv to me? It looks like it has a wire to it and costs $40. Should I replace it? What is this long tube in the intake. Does it need to be cleaned. Also it appears I do not have a egr valve or dpfe
 


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Positive Crankcase Ventilation(PCV) valve wouldn't have a wire, just a vacuum hose.

All internal combustion engines have "blow-by", when a cylinder fires some of that expanding gas, that gives you power, will "blow-by" the piston rings and go into the crankcase.
The blow-by also vaporizes some of the oil on the cylinder walls, and it creates a positive pressure inside the crankcase and valve cover areas.

In the past engines would have a Vent tube on the lower block or upper oil pan to release this extra blow-by pressure and oil vapor, it would just go out into the air and condensing oil vapor would drip on the ground.

This Vent was eliminated and the PCV valve was added to reduce air pollution, the PCV valve pulls the extra pressure and oil vapor(blow-by) into the intake to be burned in the engine.
There should also be a secondary vent tube that runs from the valve cover or oil filler tube to the air filter or air plenum, this relieves any extra pressure.
As engines(rings) age they allow more blow-by.
Blow-by pressure causes oil pan and valve cover gasket leaks, so keeping PCV valve/hose and vent hose clean will help prevent those pesky gasket leaks.

There would be no need of an electric PCV valve, so not sure what you have?


Exhaust Gas Recirculation(EGR) system helps reduce emissions at higher RPMs, whether or not an engine has an EGR system depends on when and where it was sold and also it's emissions at higher RPM, some engines needed it others didn't, some states required it others didn't.
 
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modelageek

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RonD thanks for the info. Rockauto shows a heated pcv for $35. Here is a picture of mine with a wire attached.
 

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RonD

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Sorry forgot about those, lol.

Yes, there are heated PCV valves, some use electric others have a small coolant hose around them, I think the 4.0l used coolant for preheating.

The reason for those are for colder climates, when it is cold out, below 40degF, the PCV valve would be cold at first startup and oil vapor would condense on its internal surfaces until it warmed up, this would cause it to clog up faster, and the PCV valve can never get hot enough to re-vaporize the condensed oil, so process is just repeated daily in cold weather, so coating of oil builds up.

Do you need to replace with heated PCV valve, no, save your money and just remember to clean the PCV valve more often during cold weather.
While the heating is a reasonable idea I don't think it saves any more than a few months off a cleaning schedule, but really up to you.
 

modelageek

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RonD thx again for the info.
 

modelageek

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What made you ask the question?
I am not sure?. I have a rough idle and I am chasing a very occasional p0304. I am pretty sure I need new heads but I am Covering all my bases first before I pull the heads.
 

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PCV valve wouldn't cause that but still a good idea to clean them once a year.

Ford Coil packs can give intermittent issues, you can test them with an OHM meter.

Seafoam in the fuel tank can clean up dirty injectors, I do it once a year since I run regular gas that doesn't have injector cleaners added.

Also next time it's dark, open the hood and fire up the engine, watch the spark plug wires for arcing, little blue lights, it means they are getting old and starting to crack.

Heads are pretty serious issues??
As far as I know they can't cause rough idle or P030X codes without other more serious symptoms.
 

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Modelageek----what were the part number or part numbers that RockAuto was showing for the heated PCV valve?----thanks in advance
 

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While it's not needed in warmer weather replacing the PCV with a non-heated unit will cause a check engine light.

This is one spot where you could fool the computer into thinking it is still there. The heater in the valve should have a resistance value of 10 to 35 ohms. If you go to Radio Shack, get a 20 ohm resistor and solder it in place of that connector the computer should think the valve is still there.


As for your missing EGR system, it's not missing. It was fairly uncommon for non-California Rangers to come equipped with EGR after 2000.
 

modelageek

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PCV valve wouldn't cause that but still a good idea to clean them once a year.

Ford Coil packs can give intermittent issues, you can test them with an OHM meter.

Seafoam in the fuel tank can clean up dirty injectors, I do it once a year since I run regular gas that doesn't have injector cleaners added.

Also next time it's dark, open the hood and fire up the engine, watch the spark plug wires for arcing, little blue lights, it means they are getting old and starting to crack.

Heads are pretty serious issues??
As far as I know they can't cause rough idle or P030X codes without other more serious symptoms.
Modelageek----what were the part number or part numbers that RockAuto was showing for the heated PCV valve?----thanks in advance
While it's not needed in warmer weather replacing the PCV with a non-heated unit will cause a check engine light.

This is one spot where you could fool the computer into thinking it is still there. The heater in the valve should have a resistance value of 10 to 35 ohms. If you go to Radio Shack, get a 20 ohm resistor and solder it in place of that connector the computer should think the valve is still there.


As for your missing EGR system, it's not missing. It was fairly uncommon for non-California Rangers to come equipped with EGR after 2000.
thanks for all the info.........I cleaned it out and it seems find.....it was not even dirty......I definitely can't have a cel with inspections and all in the Peoples Republic!

Adsm08 thanks for the info on the EGR! I was not aware of that!

I cant remember the part # but it was in emissions for my 2004......about $40
 

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