any of you that have had a faulty IMRC and had it replaced ,may have not needed to have had that done! went to the track night before last and was surprised by my low 1/8th times and mph and ultimately my 1/4 mphs were off too...i just had gotten my car back from the dealer where i had replaced the two half shafts under warranty as well as a motor mount and my knock sensor...the KS is located below the upper intake manifold...so i knew right away when i discovered at the track my plenum was not opening that it should be something simple,a disconnected wire or something similar as it worked before the dealer got it...i rev'd the car and nothing ..put my hand on the acctuator and after a couple times it fired...i then noticed if i just helped it alittle it would open just fine...so i proceeded to look for a wrench to loosen the cable so there was a little slack just before the motor would trigger...one the back of the upper intake nearest the PS pump there is an adjustment screw i didnt find a wrench to i adjusted that and it was enough that the motor would now open the plenum...my MPH went up 3 and ultimately i got a new best of 102.2 but no traction my best 60 was 2.1 and never did better than 14.0 ...i think my ECU needed more time to create new a/f's for the increased air flow in the rpms above 3800 where as for the week leading up it would not have been opening....

long and short if anyone ever thinks there IMRC has failed try giving it some help to open and see then if it works then it's a matter of adjusting the cables....

 

whats imrc stand for??

 

Intake Manifold Restriction Controller? something like that

 

US guys with Blowers just disconnected ours, problem fixed...

good find TypeR, I was under the impression the IMRC either worked properly or it did not...

 

I know this has been mentioned before but how do I check to see if it is working properly? Last time at the track my times seemed a bit low...It was also warmer though...

 

The IMRC controls the second stage of the intake.

It activates at about 3200 RPM to change the flow patterns.

Do a search for mystery mod and you will see some pics with the cover off

 

INTAKE MANIFOLD RUNNER CONTROL

 

yeah, but if you help like you said, what is to say that the initial reason for it getting stuck won't happen again. if your in dire need of a quick solution, than that would work, but you have nothing to lose by getting it replaced. you might also risk not having it covered if the service says it was tampered with. good find though, it took me a while to find out my valse was not working, wish i knew about this at the time.

 

the initial reason was tech removed my upper intake and when replacing it did so with the cable too tight...the screw i mentioned i adjusted could easily come loose and allow this to happen to you or anyone else...it has a bolt that snugs it but i was able to loosen that by hand...

 

oh, that's understandable. mine went without a direct cause.

 

The fuel trim adjustment is irrelevant of RPM. Also, the ECU would most likely be in open loop when the IMRC is actuated. It doesn't take too much throttle input for it to go open loop.

 

excuse my ignorance but is open loop constant?meaning does the car run at different settings based off of the short term/long fuel trims when in open loop?

 

It means the ECU ignores the O2 sensors and does not adjust the fuel trim values.