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· Registered
8 Posts
Discussion Starter · #1 ·
Here's the issue, and I'd appreciate any feedback:

Usually happens after the car's warmed up (2003 with side bags & Nav system)... I'll get to an intersection, and after being at a full stop for a couple of seconds, I'll feel the gas engine and transmission pulse lightly and erratically for a few seconds... up to about 7 seconds... and then stop. Sometimes it'll start up again, sometimes not.

It's one of those frustrating occurrences that you're SURE that if and when you took it to the dealership, you wouldn't be able to reproduce.

You might ask, "Whaddayamean 'pulse lightly?'" It's light enough that a passenger wouldn't feel it... it's almost felt through the brake pedal. A pulsing that's akin to the pulsing of ABS brakes when the system is engaged... but again, VERY lightly.

Common? Anyone else notice anything like this? You think it will be serious enough that Toyota will eventually declare it a total loss... clearing the way for a new 2004? :lol:

Any thoughts?

· Registered
40 Posts
I have had the same thing happen with my 2002. It usually happens when I come to a stop using light pressure on the brake pedal. If I push harder on the brake pedal it does not do it. If I push harder on the brake pedal, while stopped, the pulsing will stop and the engine will shut off.
My guess is that the car is trying to decide whether to shut the engine off or not and is changing it's mind. If I watch the screen, while the car is pulsing, I can see that it is applying power, on and off, to the electric motor.

· Premium Member
2,439 Posts

sounds like one of two things:

If you just stopped after driving at
highway speeds for a bit (say, a
traffic light on a 55MPH highway, or
at the end of an offramp), you could
have a bit of pulsing, often more
discribed as "dieseling" - there's
still a bit of fuel left headed to the
gas engine, and it's better from an
emissions point to have the engine burn
these last drops off rather than have
it go out through the exhaust. Sorta
more like an engine stutter.

The other, more common, thing at a
stop is sort of a pulsing, or a "dancing"
Prius. If you watch the Energy Monitor,
you would probably figure this one out.
The Prius has a simulated automatic
transmission creep. Power comes from
the battery, through the electric motor,
to power the wheels. At a stop, if
you remove your foot from the brake
pedal, the Prius will creep forward a
bit. If you push hard enough on the
brake pedal, that'll cancel the simulated
transmission creep, so when you take
your foot off the brake the car will
stay put. The pulsing that you feel is
the transmission creep trying to move
the car forward, bucking against the
light brake pressure of your foot on
the brake pedal. Press harder on the
brake pedal to cancel out the transmission
creep, and the pulsing will go away.
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