Engine/transmission pulses on my 2006

I'm wondering if it's a tank of bad gas, or a fuel filter issue, or perhaps the fuel pump(s) is/are going...? That's what I'd check if my Pinto exhibited those symptoms...but what they mean in a Prius is anyone's guess!
[smile]

In the Pinto, I'd probably replace the fuel filter and do an output test on the fuel pump to make sure it's functioning correctly.

A surge at idle can sometimes indicate a vacuum leak in the downstream part of the intake tract, but that doesn't sound like what you've described.

I'm guessing it's either an air or a fuel issue...or, more likely, an air/fuel mixture issue.

Perhaps the mass airflow sensor is not working correctly, or the fuel pump(s) are incapable of supplying adequate pressure and/or volume when the engine is working harder...?

Sounds to me like the mixture is not consistent and is going from lean to rich and back again.

 

I have that too. Exactly as you described it. but i'm trading the car hopefully this weekend.

I've lost the love.

 

I don't think there is anything wrong with your car. I have an '06 that exhibits the same behavior in cold weather. The colder the weather, the more pronounced the pulsing. For me, after the car warms up, the pulsing ceases. My theory is that the vvti, which is hydraulically controlled, doesn't operate properly at low, particularly sub-zero, temps. Perhaps switching to a lighter oil during the winter would solve the problem?

 

It's a 2006 and still under warranty, isn't it? Ask a dealer.

 

<div class='quotetop'>QUOTE(Bill Merchant @ Jan 25 2007, 10:52 PM) [snapback]380972[/snapback]</div>

My dealer said they "couldn't replicate the problem." I'll take it in again knowing that other folks are having the same problems.

 

You may want to leave the vehicle overnight with the dealership so they can try to duplicate the concern in the cold morning.

 

I have an 06 and it runs fine even in "cold" weather (5F this morning for example). When it's really cold the prius doesn't use the battery (much) so the car is a little more sluggish but doesn't stutter! And I never warm up the car before driving, I simply hit the start button and drive.

As other have said I would take it to the dealer and have it checked out. This is not normal car behavior.

 

are you talking about the speed accelerating and slowing? or the engine rpm?

no check engine light? vvti causing a problem would trip a code of some sort.

 

I'm in the market of getting a more efficient car....

I went to go test drive the PRIUS today and the only thing i did not like is when i was on the express way ...

I FELT THE SAME THING

When the accelerator was depressed halfway while accelerating the car reved up and down almost as if it were stuck switchinge BTWN two gears...


well

thats the only think I DIDN"T LIKE

I may just end up getting the yaris

unless anybody has an answer to this

 

<div class='quotetop'>QUOTE(Synergy @ Feb 5 2007, 05:17 PM) [snapback]385799[/snapback]</div>

I am guessing you are referring to the continuously variable transmission - a prius does not have gears per se. This is a technological + and not a minus.

If I were you, I would not worry about that feeling - it is just that you are not used to the throttle pedal yet and so, as you were slightly moving your foot on the gas pedal, the computer was adjusting the gear ratio / engine RPMs to provide optimal acceleration.

As you get comfortable with the car - this audio sensation of surging will be much less and is not relevant to the operation of the car. You will notice that it was just a sound and not an actual car acceleration / deceleration issue.

 

I have the same thing happening! I notice it on the really cold mornings. The surging is a bit unnerving, especially when in need of power (when pulling out of a side street) and it isn't there! It happens even after my 20 mile Warm up ride in my commute - i ususallu let things warm up a bit before I take off in the morning, drive 20 miles to doggey day care and then another 5 miles to work. The pulsing and stutter happen after the first 18 miles, going up a long hill at hiway speed, and again in town when in "winter stealth" (ICE kicking in due to temp, i think). It kind of freaks me out but i thought it was just me.
I'm glad, I think, that others experience this but is this "normal"?????

 

<div class='quotetop'>QUOTE(Shane @ Jan 24 2007, 02:41 PM) [snapback]380172[/snapback]</div>

The stuttering sounds like the TCS kicking in when you hit a slippery spot. Try easing off the gas a little.

Do you really mean the *car* accelerates and slows? Or do you mean that the engine is revving up and down?

<div class='quotetop'>QUOTE(Synergy @ Feb 5 2007, 09:17 PM) [snapback]385799[/snapback]</div>

Completely normal. The engine is putting out more or less power as needed moment-to-moment. Unlike a conventional car, the Prius' engine RPMs are not a simple function of road speed.

The traction control is a different matter. When a drive wheel starts to slip the Prius shuts off power for a moment to protect the electric drive motors. The solution is usually to just ease off the gas.

Some people expect to get out of snow or oncoming traffic by stomping on the gas and spinning their wheels. This does not work in a Prius. On the other hand it is impossible to stall a Prius engine. If you're afraid of losing traction when going up a slippery driveway, try going slower. 1 MPH is perfectly feasible.

 

<div class='quotetop'>QUOTE(Synergy @ Feb 5 2007, 07:17 PM) [snapback]385799[/snapback]</div>

Yea.. it sounds like your not used to the CVT Transmission.... did you watch the speedometer while you "felt" like you weren't going anywhere?. be careful or you'll be going 90 before you know it!....
Now that I'm used to it.. I feel like all other cars are model T's and very primitive .... I ride next to cars that pick up speed and then slow, pick up and then slow as thier transmission does its "standard" thing... quite comical!... although useful for racing or extreme off roading, having to switch gears is old school big time.
These are so smooth and powerful!....
I encourage you to take it out again and look closer this time!


I have felt similiar also... but its only when I floor it from a dead stop and its cold.
In the mornings the roads are damper from night mist and oils that mix... I just assumed my tires were trying to slip....

Maybe its something else.... I'll have to pay better attention.

 

<div class='quotetop'>QUOTE(richard schumacher @ Feb 6 2007, 11:03 AM) [snapback]386049[/snapback]</div>

I was glad for your posting because I experienced traction control operating for the first time when I went out my snowy driveway a couple of days ago. Whenever the traction control kicked in, the ICE appeared to either lose revs or cut out completely. That had me worried. Now, I am almost hoping for more snow and ice here in Connecticut so I can utilize the transaction control as you suggest..."just ease off the gas." I found it interesting that you say if is impossible to stall a Prius engine. That was what I thought was about to happen on my driveway. Of course, it didn't happen.

 

Same problem here. I noticed it happening a few weeks ago, so I am searching for answers. I know my prius well as it has 248,000 miles and it has never surged before. I first noticed it surging in the morning, but have also noticed surging in the heat of the day. When I noticed it in the middle of the day, I tried putting the accelerator to the floor to see what would happen. It continued to surge as I accelerated, at regular intervals, say every 2 seconds, but not consistently throughout the day. Make sense?

 

can you make a video?