Hi Tom, It's hard to diagnose a car over the Internet. However, to answer your question specifically, the absence of the heat tubes should NOT cause the car to pop when cold. I assume, because you have not said otherwise, that the engine does NOT pop when it's warmed up and hot ? If that is the case, I'd take a look at the choke settings. The absence of heat tubes will mainly cause the chokes to open up much slower than they normally would if the heat tubes were connected. John Hertog Sag Harbor NY -----Original Message----- From: Chrysler300@xxxxxxxxxxxxxxx If these parts are missing on 300F ram intakes would this cause the engine to make a popping sound when engine is cold as you take off.The parts missing are the two heat pipes and one heat inlet elbow.Would using a set of hotter spark plugs solve this problem thank you Tom catskill ny. To send a message to this group, send an email to: Chrysler300@xxxxxxxxxxxxxxx For list server instructions, go to http://www.chrysler300club.com/yahoolist/inst.htm Yahoo! Groups Links <*> To visit your group on the web, go to: http://groups.yahoo.com/group/Chrysler300/ <*> To unsubscribe from this group, send an email to: Chrysler300-unsubscribe@xxxxxxxxxxxxxxx <*> Your use of Yahoo! Groups is subject to: http://docs.yahoo.com/info/terms/