4kqs Accelerator Problem Update

Huw Powell human747 at attbi.com
Wed Sep 4 04:17:22 EDT 2002

> I had a chance to look at this a little more here are the symtoms;
> The initial problem was the accelerator pedal going soft and the car stalling.
> I wish I was driving at the time to have a little more data but I wasn't.
> It Won't start it has spark and smells like it's getting fuel, weather it's
> getting into the cylinder I am not sure.
> It seems like the  throttle has very little resitance but when you press the
> pedal it opens the mechanism on top of the throttle body operates.
> The Idle control valve seems to make a gurgling noise that I never noticed
> before, then again I may just not have noticed.
> Is a broken spring on the throttle body linkage going to keep the car from
> running? The spring did not look broken, but would explain the soft pedal.
> Could this be something  like a blown fuel injector fuse ?
> How often does a idle control valve go bad and could this be a problem ?

Whoa betty, slow down...

OK, the car won't start.  You have spark, is it a good, bright, spark?

Fuel?  Only two ways to tell really, stick your nose up the exhaust pipe
and sniff for it or pull a spark plug and look/sniff for it.  other than
those places there should be no smell of gasoline on a car.  I hope
that's where you're smelling it.

Now, air is the third ingredient, right?  Even with a non functioning
ISV, and a shut throttle, enough air can get in to start the car unless
it is rather cold out.

You could have too much air, or not enough, for the amount of fuel being
delivered (this could be said vice versa, to be more correct in the way
CIS works).

I'd watch that throttle linkage carefully - is it moving back and forth
smoothly in response to the pedal?

Pull the black boot off the throttle body and watch the butterflies.
Are they closed at rest?  Is one opening first, most of the way, then
the other larger one opening after a lot of pedal movement?  Do they
they then close smoothly?

Undo the other end of the boot and look at the air plate.  grab the nut
in the center very gently, can it be lifted with a little effort (not
too easy, but not sticky, grindy, etc.).

(Clean all these metal parts carefully with some carb cleaner and a
cloth while they are exposed)

Check the "spare" fuse in the side of the fusebox... check the cap and
rotor condition... look for a big switch that says ON/OFF... oops, no,
that won't help...

Anyway, start back at the beginning, basic air/fuel/spark stuff and
report.  The engine will start and run without the ISV, you just open
the throttle.  It will do the same without an accelerator cable, just
operate the throttle manually.

Huw Powell



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