Hi all ! Hope someone might give a little advice.First time this old 2003 ranger ever gave me a check engine light.Turns out there is a problem with the EGR system.Code PO400. Too low flow,possible causes:Blocked passage,bad valve,solenoid faulty.Anyways was told by a very reputable shop that the 5 speed manual trans. either has to come out,or at least loosen the mount enough to gain access to the valve.Looks like it'll be needing a new valve cover gasket anyway,and my question is this.It seems like there might be access once the intake manifold/assembly is removed.That in itself isn't an easy task,however something I might tackle myself.The truck has 79,600 original miles and has not asked for much,hate to either spend too much,or give up on the old girl.Any replies or ideas would be welcomed,Thank You.2.3 liter engine.

 

Welcome to the forum

You have a 2.3l 4cyl Duratec DOHC engine, used in Rangers from 2001.5 to 2012

This is a Mazda L engine and was designed for transverse mounting, i.e. FWD cars

So EGR valves location would not be a big issue mounted sideways, but in a Ranger it is NOT mounted sideways, so is a big issue to get to

There is also a coolant line and fitting on the "back side" that should be changed when you have access because it will leak over time.

Yes, you should be able to get to EGR and coolant fitting, with intake and valve cover removed.
I have never done it but it "looks" doable.

P0400 in no way hurts the engine, if engine starts to ping/knock then that would be time to get it done sooner than later.

The EGR system lowers cylinder temperatures when engine is under load, this prevents spikes in NOX(toxic gas) levels that occurs as engine cylinder temps rise
HOT Exhaust gases slow down the burn time, so "cooler running" using HOT gases, go figure, lol.

It also allows 87 octane fuel(regular gas) to be used in higher compression engines, because cylinder temps are kept lower so 87 octane doesn't self ignite, i.e. pinging and knocking

 

What coolant line should be replaced in the back? I ask because I just had everything off..had I known of this leaky fitting I would have changed it...lol. Not even sure mine is leaking but want to see. Any pictures or anything like that of said hose/fitting?

Thanks
Nigel

 

Quick look didn't show any "Back of the head" pictures

But this thread: 2001 2.3 Duratec - Difficult hose replacement question - The Ranger Station Forums

Has a picture of the whole hose assembly that runs around the back of the head from passenger side to drivers side, the "T" on the drivers side was also a known issue.