73 1/2 911T idle problem
 

can get it started, but won't idle or run below 2000rpm, will backfire and stall below this, checked all the obvious...fuel pressures, timing, new plugs, petronix, etc..... ideas???

I had something similar going on a few months back. I had to have the hand throttle lever pull up just to keep it at idle. If the lever was pushed down the engine idle would surge and finally stall (mine was not backfiring though). The cure was new bushings at the linkage housing on the rear of the engine. Hope this helps.

Air leaks? Poorly seated backfire valve?

+1...this is what i did to cure that problem..............

http://forums.pelicanparts.com/uploa...1371792521.jpg

914-423-211-00-M260
Bushing for Throttle Bell Crank on Transmission, Brand: O.E.M. Note: This brand is the original white plastic material. [More Info] [view in catalog]
Brand: OEM
$3.25

you will need two of these or you replace the whole bloody engine like "al" did for a few dollars more...