http://home.flash.net/~ivc1/cobra/imrc.html
This is what an Intake Manifold Runner Control IMRC that the P2004 DTC refers to. It's for a 4.6 litre, but it's a Ford. I didn't know the 2.3 L had one let alone what it was. Apparently, they get dirty and can stick open or closed.

<TABLE cellSpacing=0 cellPadding=2 border=1><TBODY><TR><TD vAlign=top align=left bgColor=white>P2004 - Intake Manifold Runner Control Stuck Open (Bank 1) </TD><TD vAlign=top align=left bgColor=white>This DTC is set when the IMRC is commanded closed, but the IMRCM indicates open. This DTC replaces P1518 and P1537.</TD><TD vAlign=top align=left bgColor=white>

• IMRC monitor signal circuit shorted to PWR GND or SIG RTN.
• Damaged IMRC actuator or solenoid.
• Damaged PCM.
• Blocked vacuum hoses.

</TD></TR></TBODY></TABLE>

I wonder if the new 4.0L Rangers are so equiped.

 

Look what I found on the link
http://www.motorcraftservice.com/vdi...f/obdsm206.pdf


The Intake Manifold Runner Control (IMRC) is a system which uses dual intake runners to supply air to each
cylinder. The secondary runners are normally closed, but the PCM opens them under high rpm conditions when

the driver is demanding additional power from the engine. The IMRC system can be actuated using a single

electric motor or dual vacuum motors. The IMRC system is functionally checked by monitoring the runner control

plates using switches. If the actual position of the runner control plates does not match the commanded position, a

malfunction of the IMRC system is indicated.

 

P0XXX codes are government mandated.

Beyond that, manufacturers can add whatever they want, whether it be P1XXX, P2XXX, P7XXX.. whatever...

I'd imagine the P2XXX codes were introduced in CAN systems.

 

TEAMWORK! This is what it's all about and is the main reason why I am proud to be associated w/ you folks @ FTE!!




mike yates: You see! Great group of people busting their buns to find a resolution for you!!
Not every question has a immediate solution...and I know it's frustrating as 'ell because we all want a resolve, working together "WE CAN MAKE IT HAPPEN"!

 

You absolutely right crazy paw. I know more now then I did before I came here. Thanks everyone for the input. I've decided to pull the intake off and see what the hell I've got going on. I'm thinking if the IMRC is stuck open(and I think that's the case) then it shouldn't be that big a deal to just leave it and ignore the code. What do you guys think?
Thanks again fellas.

 

sounds good. It looks to me that it's main operation is at high throttle opening. before that, it's normally closed. I suppose if it's stuck open(depending on how much) it would lean things out, but it sounds like your engine's running good, so not much to worry about till you do that.

 

Before you pull the intake manafold, you could consider, with the engine running, SLOWLY ingesting something like "Seafoam Engine Tune", at a up stream vacuum port, say around the throttle body & see if it would clean things inside the intake manafold up enough, to free up whatever is stuck.

The Seafoam will tidy up the intake valves & combustion chamber too, Just carefully follow the directions to SLOWLY ingest it, so the engine doesn't get so much in one gulp, that it hydrolocks & bends something up.

Maybe use something like a metal sports inflation needle, ( the kind used to inflate basket & foot *****, that has the small holes in the end of the needle), attached to a length of tubing, one end at a vacuum port upstream from the problem area, say, around the throttle body, then dip the needle into the Seafoam, to let the engine get a good 'sniff", but not long enough to stall, or hydrolock the engine.

Just some thoughts to ponder!!!!
Let us know what you decide & how it goes.

 

If there's an issue with the intake manifold runner control system, it's probably better to address it sooner than later. The IMRC is an integral part of the air intake system and the engine cannot run to full potential without it functioning properly.

Here's a description of the IMRC's purpose:

 

I was just re-reading that IMRC description that I posted earlier. It seems that the fault signal(either stuck open or closed) is sent to the computer via 'switches' that monitor the assembly. I vaguely remember a reference while reading up that those switches can stick also after being activated.

ie. You go full throttle for a bit. The switch swings open, telling the ECM that its full open. Not a problem so far 'cause the ECM sees that the TPS is indicating wide open throttle(normal). You ease back off the trottle, The IMRC swings closed, but the switch is stuck in the open position, setting the DTC. Capish . That's why you notice no problem with the engine IMO.

If you pull the assembly, I'm sure you'll be cleaning the works anyway.

Mike said,
I know more now then I did before I came here. Thanks everyone for the input. Thanks again fellas.

Your welcome, I'm glad I could help, and your right. I got on here to learn more about the Ranger(I'm buying a new one you know ), and wanted to get caught up on the way Ford's put the thing together. I got more than I bargained for. When I worked in the chemical industry, troubleshooting equipment, we had NOTHING like a 'forum' to help. The internet was in its infancy then. What I pay for my connection is worth it. We had to rely on salesman and 'tech' guys that had little hands on industry experience with the gear(frustrating).

Very few inherent problems with the Ranger from what I've found(piddly stuff). Very comforting. It's mostly stuff that creeps up on older high mileage or poorly maintained truck, that can actually be avoided or easily(relatively) fixed with a reasonable "heads up" . And THAT is what this forum is all about. This threads' been a headache figuring out, but 'hey', that's a good thing. It's 'rare', and that's a good sign.

Keep us up as to what you find once you start bustin' your knuckles.

Fred

 

Sounds feasible to me, too.

 

Thanks again guys. I will look into that "Seafoam" and see if thats' something I might want to try. I've work on engines for over 30 years so I'm not afraid of pulling the Intake off if I had to. It's just not something I'm looking foward to doing.

 

HEY DUDE!

You came here @ FTE for the right thing to do/resolution, Now Don't Procrastinate, JUST DO IT...Unless your working on the HOW-TO aspect?

We people here know "What-For" so don't let that be an issue either!!!

Just being helpful, as we all are, with our best efforts brought fourth!

 

I will let you guys know what I find out. Maybe it will help someone esle out.

 

Here's an update which I posted several weeks ago.
Original Problem was a check engine light. I scanned for trouble code using a code reader and came up with the following code: P2004.
After discussing this in the forums everyone was saying the Intake Manifold Runner Control was stuck in the "OPEN" position.
Ford has confirmed this and said it would be around $600 to $800 to fix as they would have to pull the intake off and see if the actuator was broke or if the bufferfly valves were simply stuck. I found that to be unreasonably high. After talking with a local service manager he told me that if this was his truck, he would ignore this unless the engine was running poorly.
As I said before, the engine still runs beautiful, gets 24 to 25 mpg in town! You can't tell that something is wrong with it. So I've decided to ignore it for the time being. Thanks everyone here for your help. You got me going in the right direction.

 

I know this is an old topic but Im wondering if there where ever any updates on this? My 2003 is throughing the same code.