Variable intake runner length 281e?
 

WTH!
After replacing the starter and reinstalling the air intake for the m54 b 30.
She cranks up fine BUT...
it idle like Dr. Jeckle the Mr. Hide!
Meaning up and down and back again!
Commonly known as hunting for the soft smooth model she's known for.
Then I get the above stated code and results from my foxwell and Google...wfh?
Anyone here with a similar experience and solution?

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That sounds like DISA failure to me. You can remove it and inspect the flap, it should be somewhat stiff. If it flops around freely, it is definitely failed.

There are "upgrade" kits available where the marketing team behind those companies will tell you how dangerous it is because the DISA pin can fall out and get ingested in the engine. This has never once happened in the history of these engines, it is physically impossible for the pin to separate from the flap with everything installed so unless you like to throw money away for fun, ignore those kits.

The basic repair kit, ~$50 on FCP Euro last I checked, is completely fine to use if your DISA unit has in fact failed. Complete DISA replacements are also available for about $140.

Very accurate on point info and suggestions.
I've just got new o rings in the mail... didn't remedy the problem...I ve got an aftermarket disa around here somewhere, I'll install that once I find it.

After that I'll install another throttle body... hopefully I'll get the pedal to respond.
Very perplexed situation now. Feels like I'm flying in the dark by the seat of my pants!
Thanks for your input[emoji106]

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Up and down idle in most cases is a vacuum issue. Did you check the three ports on the backside? Mine has three ports plugged.

You didn't mention the pedal wasn't responding before. Typically this should be accompanied by another code and an EML light. Is it not responding at all or just slow/laggy to respond?

Sure did yep...
2 of the three ports are plugged yes.
The smaller one has the hose routed to the canister. Canister then has hose routed to the back of the car to sensor which controls the exhaust flap? I think [emoji848]

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You're right...I was caught up in the ideling.
But the code now is #71 and this tells me something about the DSC...now more research...good thing I'm on vacation! Damn!
Oh! And on one search...I got faulty
Kickdown switch...this should be interesting.

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Will you replace the DISA valve? Mine is coming up on a replacement. I can see oil seep through the part seams. Who makes a good replacement?

Slight improvement with replacing the disa valve...m54 still hunting for smooth idel... I'm at a loss. Car starts fine. Going to replace the throttle body. But first I'm going to look over the wiring for the ECM [emoji52]
Thinking something not fully connected.

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Any cracks visible on the intake tubing? MAF sensor connections?