IMRC cleaning/codes

[Steve491]

I know, I know. Another IMRC thread.
I've read all about removing the plates or just cleaning them up but I'm curious about how they are actually monitored by the ECM. I believe there are trouble codes for left and right bank, stuck open or stuck closed. Somebody correct me if I'm wrong. If that is indeed the case, how does the ECM know this? I can only assume a signal from the IMRC control box in the intake unless there are sensors on the shafts themselves. As you can tell, I haven't taken mine apart yet. The car runs great most of the time especially once I open them up a time or two, but sometimes they seem to be lagging, hence a sputter. No codes have ever been thrown, at least the check engine light has never came on. Any of you guys that have info on 96-98 Cobras would be much appreciated. thanks Steve
:SNSign:

 

[WhiteCobra95]

There is a position sensor in the module. A friend of mine had similar issues on his ’96.

I’m pretty sure the IMRC’s are considered a comprehensive component since they're required for meeting emissions. This means that they have to be diagnosed by law. However, in a case like you described with intermittent failure (IMRC not always opening), you might not get a check engine light right away, but you will notice the power loss at WOT. The ECU usually needs to see multiple failures in a single drive cycle before it sets a DTC code, and then the same failure in multiple drive cycles to set a MIL light.

I hope this is the info you were looking for.

 

[Steve491]

WhiteCobra95, Thanks for the info, that's exactly what I was looking for.
Thanks, Steve