Our Miata recently had the check enging light come on so I took it to get the codes read and here's what they were:

P0037 O2 sensor bank 1 sensor 2

P2004 Intake Manifold runner stuck open

I've looked around and found something on a mazdaspeed miata with the runner stuck open code but they seemed to think it was something to do with a boost gauge he had put in. Ours is not a speed.

Does anyone have any clue what I should be looking for. Some pictures would be great. The car is not sluggish at all, I feel no problems when driving or idling. Should I have the codes cleared and see if it was a false alarm?

Any help is greatly appreciated.

-Neal

 

I had a problem w/the MAF sensor in my 3andit was showing 5 different codes pointing to different things.
I would be most concerned about the O2 sensor... the only one that seems makes sense.
Other than that....? I wish I had more info to offer you, but that"s all I got.
Does your Miata have a secondary intake runner throttle plate the way the MZR engines do? If so, perhaps that too is something you might look into?

 

Is it possibly you have a bad check check valve? The replacements have a yellow dot.
There is a TSB on this, for 04/05 models. It is unlikely to be a false alarm.

Good luck,

Martin