can be caused by many things.
for sure its bad deal
surging in general is a sign of lean running.
but on efi , it is far more complex.
a stuck open EGR will make idle impossible too.
the list is huge.
racings-or-highIdle
one guy just had the vacuum nipple to the dash pot clogged up.
i guess, unplug the iAC see if it stops.
if it does then eCU is causing the surge.
if not , then engine is lean.
idle on this eFI is last thing in the world to fix. (words in FSM)
all other things must be good first.
mixture, steady vacuum in induction (no leaking valve or stuck).
good compression on all 4 cyl.
IAC , both working and not clooged or jammed up.
questions:
hot or cold, or both.
i bet hot only.
is CEL lamp on at KEY-ON-not-starting, then goes out after starting?
tune up this in last 50k, ever?
miles.? total on car.
are you in North American continent? Tracker, yes.
this car is 96 and as such then it has OBD2, and as such you can
connect a scantool and look at all sensors ,and determine if any are crazy.
if a sensor is bunged then the ECU will dial up crazy mixtures.
the results of which can be bad idle.
the IAC can only control idle within certain ranges, if the range is exceeded
the 8v , tries over and over to unstick the IAC, thus the ECU/IAC server surge.
so unplug it to tell.
the 8v will run all day all year with an air leak.
it just races, and the iAC can not lower the air to compensate.
what is the rpm cold then hot.?
2000 cold
1000 hot.
or 1200 cold and 800 hot and surging by how much.
a sick engine will not idle correctly.
93 1.6 idle problem
Linear Mode
