Still have some problems - ahy ideas?

[Bruce Plecan]

----- Original Message -----
From: Roger Heflin <rah at horizon.hit.net>
To: GMECM <gmecm at efi332.eng.ohio-state.edu>
Sent: Wednesday, December 08, 1999 12:10 AM
Subject: Still have some problems - ahy ideas?


Too lean at the bottom of the temp correction, would be my first place to
start.
What kind of temp for spark corrections can you make?.
Once the engine gets some heat then things begin to even out.
The taper on the IAC pintle is about as course as course can get when
retracted, it's role is critical for a cold engine.
  This is also, along the lines of what I've been talking about with setting
the initial up to 10 from an oem of 6 or 0, and then taking the difference
out of the tables.
Grumpy

| Ok,
| My car is still not running quite right all of the time.
| Here is what I have.  On a cold start (cold engine) it won't idel
| right, I need to manually keep the rpms up.  It will run this way for
| 5-8 minutes (the IAC will  e maxed at 160, MAP will be somewhere
| around 18-20), then all of a sudden the MAP will drop from that range
| down to 13-15 and the computer will then be able to control the rpm
| with the IAC valve (IAC is no longer maxed).    I don't see (or hear)
| any obvious vacuum leaks (I did find and fix one and it did not appear
| to change the idle).  The exhaust is not plugged to the best of my
| knowledge (!cat).   I just cannot figure out what is causing the
| vacuum to not be right were it should, and why all of a sudden the
| vacuum "fixes" itself.
| Other info: nothing like fans/learn control/closed
| loop/AC/Air/Canister Purge/EGR or any other computer values changed
| significantly except for the IAC and the MAP.  The map pessure first
| dropped along with the rpm going up, and then the IAC started going
| down.  the car being in or out of gear does not seem to affect things
| excpet it dies easier in gear (of course).  Also when it starts
| running good the engine is at 160 or so and has been there for a
| while, so things have been open loop for a substantial peroid of time.
| Any help would be appreciated
| Roger