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Discussion Starter #1
Several days ago, check engine light came on. Showed a #3 misfire.
Replaced the coil, plugs and plug wires. No joy. Check engine light again and #3 misfire again.

Checked to see if plug wire might be arching, and don't see any evidence of such. Plug wires seem to be connected well.

Pulled engine cover to check for vacuum leaks or other obvious problems. Heard significant sucking noise at center of intake near base.

I did some research of parts diagrams, and it looks like the leak seems to be coming from a control rod bushing (white in color) that goes into the valve sub assembly. There is a rod that connects that control rod to the decompression chamber body. After the engine warms, the chamber body activates the rod going into the valve sub assembly. With engine running, I can remove the vacuum line going to the decompression chamber body and the rod will move one way....reconnect the vacuum line and the rod moves the other way. Sprayed WD-40 near the white bushing, and the is where the sucking noise seems to be coming from.

I have a few questions:
1. Is this a common problem?
2. Can I replace only that bushing?
3. Can this apparent air leak cause a #3 misfire? (only on #3)
4. Should I be looking somewhere else for my misfire issue?

Any advice or assistance will be most appreciated.
Thank you in advance.
Oh...I have pics of the area and bushing, if that will help.


2009 Sportage, 98 Sportage, 2012 Tata Xenon, 1944 Jeep
515 Posts
I think you are talking about the bushings for the rod that carries the butterflies for the variable intake. Yes this is a fairly common problem. I don't think that the bushings are available separately but you can buy a new variable intake assembly.

Hyundai / Kia replaced many of them under waranty and also had a recall.
Some owners have removed the assembly and had the bushes replaced by an auto machine shop. Others have simply removed the rod and plugged up the holes. It doesn't seem to make much difference to the engine performance.

If the bushings are worn then you might want to check the condition of the butterflies as they have a nasty habit of loosening their fixing screws and dropping them into the intake.
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