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idle problems (yes another one!!!)

939 Views 0 Replies 1 Participant Last post by  Kiwi_bloke
hey all... As most of you will recall my idle problem was that of a too high when hot and too low when cold... I checked for vaccum leaks, and sealed up all tubes esspecially a big leak around the vaccum hose on the fuel pressure regulator?

This has resulted in a hot idle speed 200 rpm lower than before (800 - 900) and a cold speed of 600 rpm out of gear. Im happy!

The only thing thats getting at me is the fact that when the cars driven and brought up to operating temp, then its left for say 2 hours then started again the car will rev up to 4000 rpm, drop of abruptly then pull back up to 4000 rpm instantly. It will hold there despite tapping the accelerator harshly. Its not the accelerator cable. When the cars turned off and restarted its good as gold. (it must be turned off to fix the problem!) It does this on random occasions but most likely after the described senario....

your feed backs appreciated