Dariof

Recently I posted an issue about a slight engine hesitation under certain circumstances.

https://rennlist.com/forums/showthre...ght=hesitation


There have been other posts about this as well.

https://rennlist.com/forums/997-forum/277930-my-car-acted-up-big-time-hesitating-and-very-jerky.html

I called our local dealer out here, and he shed some light on this for me. After I explained the circumstances surrounding the hesitation, he asked "Are you a two-footed driver?" The question took me a bit by surprise because I am. So I replied "Yes."

Well, for the last week I have purposely driven with only one foot (like originally taught) and to my surprise, the engine has not hesitated/stalled/jerked at all.

The dealer explained they had this issue running rampant with the Cayenne and two footed drivers. If your left foot is not completely off the brake pedal as you give it gas with your right foot, the car will stall, hesitate, etc.

I am not saying this is the cure for all, but so far, this advise has proven correct for me. Mine only stalled/hesitated when I was completely stopped, then gave it gas (of course, I was driving two-footed and did not realize my left foot was slightly touching the brake pedal).

Hope this helps at least some of you out.

BTW: I really do not think it was ever the gas we use like so many are saying. The gas I use (Chevron and Shell Premium) works just fine in my other vehicles.

jhbrennan

There may be something to that - after washing the car, I drive around the block to try and dry the wheels/rotors, etc. If I "ride" the brakes while trying to throttle up, the car reacts very strange.

500

One footed here and had the problem...

GR997S

I was on the freeway doing 70+. Foot not even close to brake.......

gpjli2

Both feet on the dashboard here.

mdrums

Only 1 leg thus only 1 foot here!

rcg412

who drives with two feet (unless its a manual)

ChipAZ

My Grandmother did and had to have the brake pads replaced every month.

yemenmocha

Can't be the solution.

Also maybe it's just me but I don't care for the location of the brake and pedal in terms of distance from the floorboard. It's tough to get used to heel toe in this car. In my other car the brake and gas are nicely aligned when braking, thus heal toe is very easy.

Ian C

The Motronic engine management system will not allow simultaneous use of brakes and throttle so that left-foot braking for example is impossible.
Not sure why the system is set up this way - does anyone know the reason?

Dariof

Can you clarify this? If simultaneous use of brakes and throttle is impossible, why is left foot braking impossible? One can depress the throttle, and then depress the brake without releasing throttle (or visa versa). The car will stop.

So far what the dealer told me is holding true, but again I have only been following their advice for a little over a week now. Today when I was driving, again my engine hesitated. BUT, I was coming out of a parking lot and I was driving with two feet (habits are hard to break). As soon as I realized this, I went back to one footed driving, and the hesitation never happened again, because my left foot was no longer slightly resting on the brake pedal.

Ian C

Dariof - sorry - I didn't mean to say that you couldn't brake with your left foot. When I said that "left-foot braking was impossible" I was referring to the technique of braking with your left foot whilst still maintaining throttle with your right foot.
This can be effective in high speed driving as it means that you can balance the car with simultaneous use of throttle and brake - but the Bosch Motronic system on the 997 will not allow this as it will cut engine power if you use the brakes whilst still having throttle applied.

Dariof

Thanks for the clarity. That is exactly what the dealer said....that the brake will cut engine power while depressing the throttle. I was unknowingly resting my foot a little too hard on the brake . It wasn't actually braking, but I think I activated a switch which led the car's system (Motronic) in believing I wanted to brake....thus cutting the engine symptomatic of hesitation or stalling.

I hope this is what was happening in my case. It's only been a week and all is well after the dealer cautioned me about two-footed driving, but the jury is still out as far as I am concerned. Time will tell if what I was told was just BS.

Coochas

I don't think this explains the hesitation problem as most of us do not brake with the left foot. Also, people are not reporting thi hesitation when trying to heel-toe. The one time I experienced the hesitation problem there was not even a fly sitting on my brake pedal!

dstrimbu

Guys, that's weird - why would Motronic care if you're braking when on the throttle? As Dave says, heel-toe would be impossible if that's the deal...

In the latest magazine reports on the Tiptronic 997 TT, the Porsche factory drivers have been executing 4k RPM brake torque starts... if Motronic was blocking this behaviour, they'd never get a solid launch.

I'm confused... (what else is neu? ;-)

-don