That sounds like the classic plugged up idle tubes on the stock
Weber-Carter BBD you would have in there.

You can look down the throat of the carb while it is running to see if
you get sprays of gas mist out of the venturis or to see if you get gas
drips coming out.

The venturi cluster 'can' be removed from the top if you take the choke
plate out of the way.  It has to be rotated 180 or so, but it comes out.

The two brass tubes there have crimped ends that are too small and plug
up easy.  They need to be cleaned out and preferable reamed out to 0.32
using a mini drill bit or I use a set of welding torch tip cleaner files
for this that welding shops sell.

Here is a link to the test and clean instructions:
http://jeep.off-road.com/jeep/article/articleDetail.jsp?id=277064

The cause is dirt in the carb.  A kit for your carb is less than $25.00
and is easy to put in.  Make sure you get the piece of gas line between
the carb and filter clean too as this is a sneaky dirt source.  One
other is running out of gas which can suck little charcoal bits into the
float bowl from the emissions canister.

Mike
86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00
88 Cherokee 235 BFG AT's - Gone to the rust pile...
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