Very bad hesitation

Sounds like the VSC or the TRAC is kicking in because of wheel slippage...

 

Also could be ignition coils. I had an '01 galant that did the exact same thing. I took it to a mechanic and he found out thats what was causing it. I replaced it and the hesitation never happened again. Ran the way it should have.

 

No, it's the traction control system, and it's there to protect the HSD system from over-spinning MG1 (motor generator number one). There is probably oil on the road with water. This will allow the front wheels to spin up. Nothing you can do about it other than better tires for better traction. If you are still using the OEM Goodyear Integrity tires, get some better ones fitted. The difference will be like night and day.

Oh, just thinking if your car is an early 2005, it may be improved with a software change. See your Toyota dealer about this. Tell them the traction control system seems too sensitive, and ask if there's a software fix. The details are on this forum but I don't remember the TSB number.

 

VSC and TRAC are the car's stability control and traction control systems respectively. Thats got to be whats happening. Are there metal grates in front of these entry/exitways?

 

Hi Lottoman,

Yea avoid giving the car allot of throttle when your tires are on metal. Its kinda like that situation with the rookie race-car driver during the start of the Indy 500 a few years ago. Not being used to the tremendous torque of the Indy cars, he broke a half shaft right at the start of the race and caused a big mess. Mario Andretti was livid they let him in the race, let alone on the pole.

It may only have 110 hp, but at slow speeds, the Prius out torques most other cars with 185/65-15 sized tires. If the tires start to slip, the traction control will kick in, and in the 2005's its reported very agressive, with a long delay before it returns throttle control to the driver.

Supposedly the TC (Traction Control) and VSC (Vehicle Stability Control) have newer computer programs that can be loaded. The 2006 cars (with the newer programming) seem to be a little better in snow, but they still will really drop throttle on wet metal.

Last time I had my tires rotated, the technician could not back the car over the ramp. So, they had me do it. In reverse the Prius is electric only. So, I brought the throttle up slowly to three-quarters, and then it backed up over the ramp. I quickly dropped throttle once it started to move. And it coasted out onto of the garage door. The tech was attending to something next to the car, and his eyes just went WIDE open when th car jumped backward over the ramp. After he had not been able to get it to move.

In your situation, best to get some speed going, lift throttle and coast the front wheels over the metal grid, and then go 1/2 to 3/4's throttle up the ramp. As you know the Prius throttle has is very linear, and one can do very precise slow-speed control of the car with it, on dry pavement.

 

Thats the issue. You're applying havy throttle as the front wheels pass over the drainage grates which breaks the traction and engages the TRAC. Accelerate before or after the grates.