Steve Lutfy

So, I finally had a chance to drive a C7 3LT auto with the Z51 Performance Package. I got to tell you that I was a little surprized when I hit the gas. I experienced a momentary delay. Is that common? Anyone else experience that?

robertf97

Yes, mine in tour (A6) seems like you need to hold the pedal down about 300 milliseconds before it will downshift 2 gears and take off. In sport or track I think it is less.

TBIRD57

having a turbo without actually having one

checkur6

Yeah, I noticed a feeling like there wasn't a firm connection with the transmission when I would start to press on the accelerator (it did get VERY positive with more pedal pressure). Even had the trans fluid checked. Had it checked at my first oil changed and they said it was perfect. Oh well, anyway, it seems really good now, much more positive and responsive. Don't know what they did, if anything, but the car gets better and smoother with age.

Rave

No delay on my Z51. Just curious, how many miles were on the car?

Steve Lutfy

Believe it or not, only 153 miles. Wonder if this will improve with age as stated above?

Rave

Wow, that's not good. My first thought that comes to mind is possibly a problem with the Mass Air Sensor, but best to have a dealer check it out at the 500 mile oil change.

Higgs Boson

compared to a drive by cable, your drive by wire (electronic throttle body) has a different feel to it. it is much less responsive on the low end of the throttle position range and comes more alive when you get it over 60% or so.

the tables are called Driver Demand in the tune and can be altered by any tuner to make the car more responsive to throttle inputs although it doesn't really increase full throttle power.

barring any actual mechanical problem (hard to diagnose online), this is probably what you are experiencing.

SSTEVEGS

I drove a manual (Z51) and didn't notice anything like that...perhaps it is the TPS (throttle position sensor)?

SSTEVEGS

[QUOTE=Higgs Boson;1588577818]compared to a drive by cable, your drive by wire (electronic throttle body) has a different feel to it. it is much less responsive on the low end of the throttle position range and comes more alive when you get it over 60% or so.

Egads, I hope my new C7 doesn't do this....my current C6 has absolutely no lag whatsoever during any throttle range!

Kingtal0n

I've noticed that a few other drive-by-wire cars do this. Put a voltage meter on the TPS and watch what happens, it seems that when "driver demand" is low, the throttle body opens slowly at first, then gradually opens faster once it passes a certain position. My guess is this helps smooth the transition from closed to open position, so the engine response is more predictable.

tblu92

A stock C7 tune does NOT allow the throttle to go to Wide open until the RPM's are above apprx 3200-3400 RPM's
That is the reason for one of the delays
There are several others--
-The traction control system limits TQ below 1600 RPM's to below 380
Power enrichment has a delay until the car reaches 20 MPH
Power enrichment is delayed IF the throttle increase rate is too fast
Finally in the TQ response tables -- The HP is limited sometimes to almost 1/2-- below 100 MPH and 75% throttle position
As an example the stock tune at 60 MPH and at 75 % throttle position the HP is limited to 243 HP
Good news !!! all this can be updated with a real tuning software--either EFILIVE or HP- It makes a huge difference even on a bone stock car---
Basically tuning will allow the engine to make "all the power it can---ALL THE TIME regardless of the MPH or Throttle position or RPM--- !!!

0v3rc10ck3d

Ughh....really? That sucks. This is a damn super car. Sounds like a tune is REQUIRED to get what we paid for but then we have to worry about warranty coverage. Sucks.

Higgs Boson

it's definitely not a super car.

0v3rc10ck3d

Super Duper

JoesC5

A friend with a 2014 A6 has complained to me about the lag he is experiencing.

jimman

Read your manual it explains it all. Put it in track mode/race and everything is disconnected. A tuner can rem those out giving you the illusion of more HP when in reality it just F ed your active handling.

Higgs Boson

Can you explain in detail in your own words:

How adjusting the throttle responsiveness F's your active handling?

What does "rem" mean?

What gets disconnected in Track mode (sounds serious)?

How many cars have you connected to your laptop and tuned?

Can you also elaborate on any conspiracy theories you might subscribe to that tuning your car "actually does nothing?"

Thank you.

jimman

Since we locked horns though the PM's on this issue recently let me try again in a public venue to explain this. You did elaborate your extensive experience with tuning to rebut what I was concerned about. I wasn't impressed with your language when discussing this, (have a nice day, weirdo for example) so here goes.

1. Read pages 9-37 through 9-47, granted a lot of pages so focus on page 9-45 and 46.
2. Rem, an old DOS programming term for deleting a code line.
3. (What gets disconnected in Track mode (sounds serious)? read page 9-46.
4. How many cars have I connected, 2000, 2002, 2005 and my 2007 Z06.
5. Conspiracy theory, well as I explained to you that I contacted companies that have close relationships to GM, Lingenfelder and Katech both said that there is little to no gain when tuning a stock LT1, 5hp was the best attained. Then when you read responses from people that had a tune saying how much better the throttle response is and you read the parameters from the manual you see to issue.
6. That's when I believe you told me to go away with my BS.

thegame

Duh it's the turbo lag guys