Here is an example of an idle bar plug
http://www3.omnimodels.com/cgi-bin/w...I=FOXG1470&P=0
The idle bar is supposed to keep big drops of fuel from splashing on the glowing element.

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I have no idea if an idle bar plug will help your engine run better. I am thinking "No" since you're having fuel draw problems. The idle bar would be more likely to help if you were getting too much fuel at idle.

Getting the tank height "pretty close" to optimum and making sure you have proper flow is probably the best approach.