Hello All,

New member here. My truck is a 2008 f150 with the 5.4 triton. It is throwing a p2004 code. My mechanic replaced the IMRC. The code went away for about 200 miles. It then came back on. I then cleared the code once and it came back immediately upon startup of the truck. I cleared it one more time and was off for about 50 miles. He came back to look at it while the code had been cleared. He ran his diagnostics scanner on the computer and he showed me how the valve was opening as the RPM increased, and closing etc. 150 miles later it came back on again. It only seems to do it on startups. If I clear it while it's running and then drive it for a few minutes the code never appears not until several days or miles later. The truck while this code is on or off runs perfectly fine. It starts fine, it idles perfectly never revs or lowers. Upon acceleration there's no hesitation or jitter or anything. The only repair I had done prior to this occuring was I had the spark plugs and ignition coils all replaced. Any thoughts?

I had thought possibly a vacuum leak somewhere or something wrong with the pcm itself.

Thanks for the input.
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rcooper4,
I see that you have had no replies so far, I am sure others will chime in when I present a guess to the reason for you DTC P2004.

From another website
"The PCM determines IMRC control based on inputs from the throttle position sensor (TP) and crankshaft position sensor (CKP)."
So my vehicle a 2007 F-150 with a 4.6L 2-valve engine does not appear to utilize a IMRC and you got my curiosity going with your post. I read your post and found it interesting that the since you changed the IMRC valve code only appears after startup and that you can clear it after startup and it does not return until the next startup. The following is a WAG. Is it possible that you are depressing the throttle while starting the engine and causing the throttle position sensor (TPS) to send a signal to the PCM that is unexpected and thus generating the P2004? I admit this is a guess but probably worth consideration.
Others with more experience with the IMRC control system will likely comment and we will get the dialog rolling

 

Thanks for your response and input. I haven't been depressing the throttle on most startups I would say. It is possible I may be unknowingly doing it. It is something to be cognizant of next time I start it up. The IMRC recently installed is warrantied so I will be replacing it under warranty perhaps seeing if it's something to do with the new part. I will keep you posted. Thus far the code still comes on at startup only.

 

I'm having the same problem, did you find the fix?

 

his last post was 5 years ago, not sure if your gonna hear from him.