High idle after start

[Jemison Richard]

Roger,

Thanks.  You may be right in which case, I've really got a red face, ha!  I
got the IAC codes from the ECU originally and have just sort of fixated on
the efi.  Sort of the same thought process that killed the Vette Rochester
fuel injection that has been so interesting to read of late on the list! ha!

I have to laugh that in 3 messages to the list I've gotten a total of 4
answers and all questions have been efi related (at least they were meant to
be, ha!).  Yet there has been a 200 (maybe a slight exaggeration) message
thread on the GM water pump.  Does this mean, readers of this list are more
in tune with water temp than efi?  Or GM more than anything else?  Just
having a little fun.  It is amazing the dialogue required to say slow the
pump down and leave the thermostat in! :-)

DISCLAIMER:
I didn't read all the thread, so if more info than that came out I
apologize.  Void where prohibited.

Rick


> -----Original Message-----
> From:	Roger Heflin [SMTP:rah at horizon.hit.net]
> Sent:	Wednesday, October 14, 1998 9:24 AM
> To:	'diy_efi at efi332.eng.ohio-state.edu'
> Subject:	RE: High idle after start
> 
> 
> From my experience (it is limits), but the ign system going bad
> (plugs, wires, or some other part) going bad will cause the idle
> quality to be really bad.  In my car (93 Z) with an optispark
> (odd computer controlled distributor, with extra sensors), when that
> part died, when the AC came on the car died, sometimes just sitting at
> a light or idling slowly through a parking light, the car would die, I
> replaced it with a new iginiton system and it idles just fine now.
> So, if you have not checked the ignition system, check it, check
> mainly the plugs and wires since I think the saturn would not have a
> distributor right?  It has coilpacks?  But check the wires and plugs,
> if either of those is bad your idle won't be real good, I was dropping
> cylinders on a V8 and that was bad enough, on engine with less
> cylinders it would be a bigger problem.  And at least plugs are cheap,
> the wires may be more expensive.
> 
> 			Good Luck
> 			Roger
> 
> On Wed, 14 Oct 1998, Jemison Richard wrote:
> 
> > This is interesting to me as I have a Saturn that is screwing up (efi
> > problems I believe) and the main symptom is very low idle.  I got IAC
> codes
> > from the ECU and (being very new and obviously ignorant of these little
> > critters) jumped out and bought another IAC.  Didn't do squat.  I've
> checked
> > for vacuum leaks (spraying starting fluid all around the injectors,
> manifold
> > plenum, vacuum lines, etc.  Nothing.  I believe this system is a MAP
> based
> > system.
> > 
> > It runs great, accelerates and top ends best of all its range.  Coming
> to a
> > stop it does OK until you fully stop and sit there a minute.  Then the
> idle
> > drops down to 300 and the car dies shortly after.  I've tried increasing
> the
> > idle by turning in the idle screw (1- 1.5 turns) - nothing.  More than
> that
> > and it really starts running bad.  I can keep it running by holding my
> foot
> > on the gas while holding the brake on with the car in gear.  But this
> causes
> > the car to heat up very quickly.    Also, as it sits around 1000 rpms
> > (running steady at first) the longer I have to sit at a light the more
> it
> > starts jerking (like missing).  It is now starting to do this a bit
> during
> > 50-60 cruise also.  Minor at these speeds but wasn't there a day or so
> ago.
> > 
> > As a side note (and I have no idea if this has anything to do with the
> > problem) I'm losing water (not much but a little).  Could be going out
> the
> > overflow from the heat ups.  Not sure.  I'm not leaking it.  That I do
> know.
> > 
> > Yea I could take it to a shop and get it fixed.  But if I'm going to try
> to
> > modify one of these things I have to know how it works.  And I should be
> > able to diagnose problems with it.  Otherwise how will I be able to tell
> > what to change?  So, any help would be appreciated.
> > 
> > Rick J
> >