[Mgs] hot idle troubles

[Aaron Whiteman]

On Jul 7, 2012, at 4:52 PM, Simon Matthews wrote:

> Maybe you still have a vacuum leak, but only when hot (something expands and
opens the leak). Or, are you driving with the choke out for the first 8 miles,
thus masking the effects of the vacuum leak?

I'll certainly look into it.  The mixture could be rich too, I recently leaned
it out when a guy on a bike complained my car smelled of unburnt gasoline.
The plugs look fine.  It was also suggested I check fuel pumps and filters,
though I don't have a problem with cutting out under load, so I don't suspect
that.

To answer Don's question from another email: yes, I have to use the choke when
the engine is cold, even in 83 degrees.  I don't have to keep it on for more
than a few seconds, but the car won't start without some choke.


Just to be clear, I want to reiterate: the problem only occurs when I drive
the car long enough to get it warmed up properly, then park it.  For the first
few minutes, the car will not idle at stops.  If I drive far enough, the
problem goes away until I again park and restart.

If the car is parked long enough to cool, I have no problems.  If I haven't
recently parked the car (and turned it off!), I have no problems.  If the
ambient is below 80F, then the problem changes: instead of just quitting, the
engine tickover drops to 500rpm.  After a quarter mile, all is normal at the
next stop sign.

In all cases, the choke is fully disengaged as the car is warmed up.  If I
press on the throttle while stopped, the problem is mitigated, but my lead
foot has a hard time maintaining just enough throttle to keep it going, while
staying under 1000rpm at the stoplight.

It could honestly be as simple as "set the idle to 850 rather than 750 and
forget it," but before I did that, I wanted to get other suggestions.

--
Aaron