Helmar

I'll be replacing my Lexus LS 600hL in September and have narrowed it down to an A6/7 or E550 4Matic.

I took a test drive of an E550 yesterday (a leftover 2012) and noted pronounced turbo lag.

I'm assuming that it was turbo lag, as it took 1-2 seconds before the car did much after tromping on the pedal.

Perhaps it was just trying to figure out what to do?

This is definately one thing I'll look for when I test the Audi later this year. I'll wait until the 2014 are available.

I'm assuming that because the Audi is SUPER rather than TURBO charged, this isn't an issue.

As a hybrid, and when I step on it in my current Lexus, the electric motor provides instant torque and the car leaps forward. Then the gas engine chimes in a second or two later.

HBH

RobC

It may well be turbo lag, but many manufacturers program the throttle response to be this way. It's a common complaint from BMW owners on normally aspirated motors. Just Google "bmw throttle tip in".

The S6 is twin turbo, but with its extremely short path from the exhaust manifold to the turbos, the lag is basically non-existant. When starting from a stop, the throttle response is very immediate, but if you accelerate immediately after braking, there is a noticeable "pause" before the computer decides to accelerate. It's obvious it's the computer because the RPM/engine sound doesn't change upon throttle tip-in. And this changes when you have the transmission in Sport (dynamic) mode.

snagitseven

The A6 3.0 6 cylinder has zero lag because, as you noted, it's supercharged. The turbo 2.0 4 cyl A6 has been reported as having virtually no lag.

Helmar

Thanks for your reply.

What about the A6/7 with it's supercharger. Any lag, or instant leap forward?

HBH

NVThs1

As Snag said, the 3.0 A6 has no lag with it being supercharged. I had the 2.7 Bi turbo A6 engine and there was a lag. I can't vouch for the current turbo'd engines, but my older model turbo A6 had a lag for sure that I do not see at all with my supercharged A6.

RobC

Since I don't have an A6/A7, I can only speak for the 2010 S4 which has no (motor) lag or throttle lag.

Basically on the S4 the drive-by-wire still feels like your foot is controlling the motor through a cable (except in cases of traction control, etc). On the S6 you can tell there's a computer between your foot and the motor interpreting what you want to do.

Helmar

Interesting, so there would appear to be two issues that can affect "Green light goose" performance.

One is turbo-lag, which, being supercharged, the A6/7 doesn't suffer from.

The other, though is computer induced (perhaps intentionally by the manufacturer) "throttle tip in" delay.

Does the A6/7 suffer from this "throttle tip in" delay?

What would induce a manufacturer (especially of performance oriented vehicles such as BMW) to add such a delay?

HBH

move_right

I can speak with some authority on this subject as I recently came from a BMW 335 with pronounced throttle tip-in lag (different issue from turbo lag). Essentially, some recent model BMWs, including but not limited to my 335, have a delay in throttle response. Press on the accelrator, and there is a short pause before the engine/car responds. Its sounds minor, but it winds up being a huge annoyance bordering on a safety issue.

When I was shopping for my next car, I paid particular attention to this issue which was one reason I chose the A6 over a 535. I find there to be no throttle tip-in lag with my Audi. Furthermore, if I drop the gear selector into Sport mode, it is even more responsive.

Helmar

I repeat my earlier question:

What would induce a manufacturer (especially of performance oriented vehicles such as BMW) to add such a delay? What's the benefit to the manufacturer, as there appears to be none for the consumer.

HBH

Grapeking

2nd on this. Still have the 2.7T in fact, and a 3.0T, and there is zero lag on the 3.0T and a more instantaneous throttle response (particularly at low RPMs).