4kq cold starting issues

[Huw Powell]

"I have this problem with my 87 4kq. it has this cold starting problem.
symptoms:  When I go to start the car from cold the engine will turn
over and catch occasionally but not enough to start the engine.  so I
turn it off, and try again, second attempt gets a little better, catches
a little more, and sometimes will continue to run but sounds like it
just isn't getting enough fuel and it is running at about 400 rpm.  if I
let it go, it sounds like the computer senses this and saves the day by
doing something to get the idle to jump up suddenly and fall back to
1000 rpm.  so... now it's idling, which it does for about 5 seconds then
it sounds like it's starting to struggle for fuel again, the idle falls
down to about 400 rpm then the computer saves the day again, jumps it up
and after all of this, it settles out and runs fine.  I have to wait a
couple of minutes though before I take off otherwise it won't accept my
gas pedal pushin' and will just fall back into the 400 rpm zone."

1 possibility: It sounds as though the static fuel setting (the 3mm hex
between fuel dist and airboot) is not right.  This is probably not due
to misadjustment, but because of air leaks in the intake tract after the
airplate.  So first, check out all the antique rubber bits in that area,
and when you think there are no leaks and all is good, check the
pressure actuator current at warm idle and see if it fluctuates around
10 mA.

2 another: ISV may be sticky and need cleaning.
3 a third: the grounds on the intake manifold may be poor.
4 more: the temp sender for the CIS-E computer may be faulty, this is
under the top radiator hose flange.

In other words, check out all the fuel/air system components looking for
anomalous behaviour... and good luck!


--
Huw Powell

http://www.humanspeakers.com/

http://www.humanthoughts.org/