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Discussion Starter #1
Well I decided to bury a topic that’s been beaten to death many times by many people. I have installed a boost gauge in my currently naturally aspirated V6. Sure enough I noticed something interesting as soon as I started the car, and went for a drive. The boost gauge responds the instant the pedal is depressed and goes to 0 vacuum at about 3/8 of pedal travel. The engine according to the tachometer lags behind the throttle. Even if you tap the gas, the boost gauge will rise and fall before the engine has started to fall indicating that the throttle has indeed closed. Now I think this is due to a combination of things, included a flywheel that’s too heavy, and a very restrictive intake. But I don’t want to hear throttle lag again. I should also mention that I have had the MSP10 update performed on my 6 that I absolutely hate, but I have no proof that it did or didn’t lend a helping hand.

Now if you argue that your car has throttle lag, I WANT PROOF. Otherwise you will be hereby expelled from the board and you car being repossessed. If you still doubt my findings I will post a video upon request.
 

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Well I decided to bury a topic that’s been beaten to death many times by many people. I have installed a boost gauge in my currently naturally aspirated V6. Sure enough I noticed something interesting as soon as I started the car, and went for a drive. The boost gauge responds the instant the pedal is depressed and goes to 0 vacuum at about 3/8 of pedal travel. The engine according to the tachometer lags behind the throttle. Even if you tap the gas, the boost gauge will rise and fall before the engine has started to fall indicating that the throttle has indeed closed. Now I think this is due to a combination of things, included a flywheel that’s too heavy, and a very restrictive intake. But I don’t want to hear throttle lag again. I should also mention that I have had the MSP10 update performed on my 6 that I absolutely hate, but I have no proof that it did or didn’t lend a helping hand.

Now if you argue that your car has throttle lag, I WANT PROOF. Otherwise you will be hereby expelled from the board and you car being repossessed. If you still doubt my findings I will post a video upon request.
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I think most of us that complain about this have automatics..... So there is a delay from when you press the pedal to when the computer reconizes it.

There is even a TSB for it.
 

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Discussion Starter #3
if it's more so in the auto's then I'd start calling it torque converter lag
 

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You didn't prove that there isn't throttle lag. You proved that there is throttle lag. You observed it yourself -- the engine lags in response to the gas pedal. You just proved that it isn't caused by the throttle-body, but rather by some thing, or some combination of things, else.

Big difference there.
 

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Ive had the throttle lag before. Ive floored it and then 3 seconds later the car downshifts and goes... Doesnt do that anymore tho after the updates and the mods i have done...
 

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Discussion Starter #6
if it's 3 seconds later then i'd say that it's a computer issue. But I don't think it's fair to blame it on the throttle body when it's not the direct issue. Sigma, that's what I meant to say. The engine lags, not the throttle body.
 

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Here's what Mazda6sMtx is trying to say:

1. Vacuum gauge needle responds immediately to pedal being pushed or released.
2. Tachometer needle lags behind pedal push/release

This indicates that, as far as the engine is concerned, there is NO throttle lag since the engine is producing vacuum in immediate response to the pedal action (as shown by a vacuum gauge that responds immediately).

What this shows is that the tachometer is slow in receiving input from the ECU.

Therefore throttle lag does not exist. What does exist, however, is tachometer lag.
 

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No, it's more than that.

I've got a digital tach tied directly into the camshaft sensor, and it doesn't respond significantly faster than the analog one in the car does. There's still a noticeable lag, particularly when the CAI isn't installed.

Just because there's vaccum in the engine doesn't mean that the engine is moving, just that it's trying to move. It's still slow to respond.
 

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sigma ur last sentence proves his point that its not throttle lag its the engine slow to respond... which side u on lol
 

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sigma ur last sentence proves his point that its not throttle lag its the engine slow to respond... which side u on lol
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The engine being slow to respond is throttle lag.

If I push the throttle and it takes 10 minutes for the engine to move, there's "throttle lag" -- there is a lag between when pressing the throttle and a corresponding action with the engine. It doesn't matter if it's caused by the throttle-body, the intake, the engine, the flywheel, or whatever. There is "throttle lag". It's just not caused by the throttle body.
 

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indeed sir..
 

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I have noticed that the lag is much more significant when the car is not moving or moving slowly. When I rev the engine sitting still, the car sounds like it is gasping for air and the lag is pronounced. When the car is at highway speeds, I notice almost no lag while excelerating, even in 5th gear.
 

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I've never complained of a "throttle lag" problem, even with an auto.

I would imagine there is a certain amount of lag present with all engines as the air going in takes time to speed up, though in most cases this would be nearly zero.

However when most people complain I don't think this is what they are really complaining about.
 

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If it was as easy to point out as some of you describe it, i'm sure this problem would have been resolved a LOOOOOONG time ago either by mazda or a company looking for good $$$$. As for blaming it on the computer though...only a ...well only someone incompetent could have designed it in such a way to take that long to retrieve data, process, and output - more than a few milliseconds would be unacceptable.
 

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I've suspected what Mazda6sMtx is saying for a little while now and I do agree with him. I've suspected that it's due to a heavy flywheel, because the lag is only noticeable at high rpms, I feel absolutely NO noticeable lag when driving normally, only when I really get on it. So I'm wondering if anyone who got a lighter flywheel could comment on whether or not the lag is reduced.
 

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It's more than just the flywheel. Adding a CAI removes a significant amount of the lag for most people, myself included. I've gone back and forth between the CAI and not a few times now for various reasons, and the difference is quite staggering. Although the problem is exacberated by the TCM programming in Automatics (largely fixed through various flashes) it's very noticeable for manual drivers because of downshifting. You have to give yourself an extra second before letting out the clutch to let the engine catch up with your throttle blip.
 

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I've driven the car up to 6k rpm even after I've installed my MAFci, and the lag at that engine speed is still about the same as before I installed it. And the 6s supposedly has a massively heavy flywheel right? I read somewhere that the 6s flywheel is 25lbs and the 6i is 20lbs.
 
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