Throttle Lag

[Retired_Ted]

New 2007 with 1000 miles (purchased a week ago). Ever since I picked up the car, I have noticed a distinct lag if I jab the throttle instead of carefully increasing the throttle. I have been gentle with the throttle since the engine's new, but, lately, I have been driving with a bit more "spirit". The car is a "left over" 2007 which means it has sat on the lot for a year with very little activity. Not sure if I have a "sticky" or dirty injector or some such thing going on. Taking it to the dealer tomorrow to have a 3M invisible mask installed and will ask if there's a know problem. Thought I'd check here first. TIA

[whitemike711]

welcome to the club first of all, and congrats on the purchase.
the lag you are having in my opinion is normal. the car does not have a lot of torque so it does not jump when you tell it too. the best way for this car to get up and go is to down shift carefully. im not the most techy guy on here, so im pretty sure others will jump in and agree or disagree.

[Retired_Ted]

Thanks for the response - I'd agree except it almost feels like a miss. Perhaps ignition related. It happens every time I "jab" (for lack of a better term) the throttle from a slower speed. I do not want to give the impression that I do jack rabbit starts or whatever, but, there are times when I need to accelerate quickly from a slow speed and that's when I get the lag. I'm coming off a '99 Miata so, I am aware what lack of torque really is :0). If it's normal, I can live with it. At this point, I feel it's not. We'll let the mechanic give his opinion either tomorrow of some other day. No hurry - I plan keeping the car for a long, long time. Love it.

[repiv]

Can you tell us from what rpm you are attempting to take off? If you mash the gas peddle from anything much lower than about 2500 to 3000 rpm, I completely expect the response you are getting. To achieve the kind of "get up and go" in the scenario I think you are trying to do, you must learn to do a rolling clutch slip take off or a full blown rolling clutch dump. If you want to fully explore the S2000s capabilities, don't get into the "this car has no low end torque" rhetoric that most kids proclaim when they try to drag race somebody on the street. I would think by your screen name that you are not a "kid". Nevertheless, a lot of S2000 "newbies" (regardless of age), haven't discovered the nuances of driving the car to take advantage of its powertrain.
Even though a Miata is a similar car (less hp and torque), it is simply a bad comparison when talking about mashing the gas from a low rpm and speed. Its redline is different. It's gearing is different. It's cam profile is different.
Once you confirm the rpm you are starting from, I can make further comment.

[asnbanker]

New 2007 with 1000 miles (purchased a week ago). Ever since I picked up the car, I have noticed a distinct lag if I jab the throttle instead of carefully increasing the throttle. I have been gentle with the throttle since the engine's new, but, lately, I have been driving with a bit more "spirit". The car is a "left over" 2007 which means it has sat on the lot for a year with very little activity. Not sure if I have a "sticky" or dirty injector or some such thing going on. Taking it to the dealer tomorrow to have a 3M invisible mask installed and will ask if there's a know problem. Thought I'd check here first. TIA


If I'm not mistaken, you have been gentle up until recent, now your driving different and the computer will need to learn your driving style. Another thing is. on the 06+ models with the limited slip, it will feel like lag as compared to previous models, but the pick up is actually the same. If you want to. you can take the slip off and it will feel more alive and different, but in actuality its the same.

[bimdub]

honestly, my opinion may be different, and arguable.......but I must say clearly that every single DBW (drive by wire) car I have ever driven......is different that a true mechanical linkage in response....this is more noticeable during the summer months with the A/C running......especially from a stop light......I complained extensively about our Subaru with this......but every thing checks out......every time......it just feels like a small "dead spot" when you first touch the accelerator from either a stop or even after coasting and getting back on the throttle.......ever so lightly......this could be what you are sensing?

if I had to compare it to old school terms.....it would be like say the accelerator pump discharge nozzle on a carb that is too small.......or has too late of a pump shot.......this of course would only make sense to guys that tune or have tuned holleys or multi carb engines.....say a Weber side draft setup? I think there is a small amount of lag between the time you put your foot down.......where the ECM is reading the change in the gas pedal and decides to open the throttle.....and then the TPS reports this back to the ECM which then makes the fuel adjustment, these things while happening very fast.......have an extra few steps in them that we just are not used to.......in the non DBW cars the throttle is cracked open with a cable and the TPS reports this to the ECM....for the fuel change......no need for the information to pass through the ECM twice.....

long story short......it just feels more connected......the old system......however the new system does have some interesting potential that can be used if not already....loads of safety possibilities.......as well as fuel conservation.....

also what limited slip are you referring to Alex? I drive the S with its Geared Torsen style limited slip and I also have the Subaru with a viscous unit....and the BMW I own has a clutch style dialed in at 60% lockup......and to be honest unless I am driving the ~~ out of them I do not notice any major difference? are you thinking of the CDV (Clutch Delay Valve)? now that certainly would be new to any Miata driver! another thought is that the Traction Control is what he is noticing? that stuff just messes with you if you are not used to it......

and once again Repiv has the answer to great starts.......the rolling clutch slip....may not be great on the clutch.....but I pulled one off recently and without so much as a squeak in the tires I felt it was the most powerful takeoff I have ever felt from the car.......

[repiv]

I think Bimdub may have hit it on the head. DBW can be a bit "disconnected" when you want immediate response. Although it might seem like the engine skipped a beat ("miss" as he called it), I think the ECU will control the opening of the throttle plate to the extent that the engine won't be allowed to miss. However, if he were to mash the gas from a low enough rpm, it is possible for the engine to get close to "bog" or lugging and is what he may be feeling.

I'm sure Alex must have been talking about "traction control". Again, I can't see it coming into the equation if you mash the gas from a very low rpm. There won't be enough torque to cause traction issues unless he was on a slippery surface at the time.

As for the rolling clutch dump .......................................... :shh: We don't want this getting out. We'll start to see newbs blowing clutches and rear ends because they don't undertand the concept of doing it right or abusing the car by doing it repeatedly. Then we won't see other car forums talk about how the S2000 is such a "no torque" wonder. We can't have that now, can we? :laugh:

[Retired_Ted]

Wow - some great information presented here. First of all, I am not a crook, I mean, kid (you have to be old enough to appreciate that slip). Almost 63 and using my social security to help pay for the car - how's that for using the money wisely? I believe I am being a bit too kind to the clutch - I don't allow it to slip for much time at all. I hate to see a clutch slip since I understand what's going on in there - I've been an avid motorcycle rider for a dozen years (BMW's, HD's, Honda's, etc) and have had to replace a clutch or two. So, I think the early engagement along with the drive by wire (my '04 TL has the same arrangement, but, it's automatic) must be what I'm experiencing. I just brought the car home from having a clear 3M mask put on the front end today and forgot to ask the guys at the dealership about the lag. If I think it's noteworthy, I'll plan a future visit to the dealer and see what he says. Thanks again for all the thoughtful responses - that's why I like forums - hope I can contribute something in the future. Anyone live near Gettysburg PA?? Might be fun to arrange a little road trip sometime.

[parkerdt]

My '06 has none of this lag when I jab the throttle. But the ECU is now well-trained to the way I drive, at almost 50k miles. It get up, and MOVES.

My '02 (which is not drive-by-wire) DOES have some of this, but I think it is ECU - it has gotten significantly less in the 5k miles I've put on the car; it is learning.

Dave

[repiv]

Anyone live near Gettysburg PA?? Might be fun to arrange a little road trip sometime.
You're 6.5 hrs drive from S2K Days in Lake George end of Sept. That's probably the most S2000s you'll see in one place at one time.

http://forums.s2kca.com/showthread.php?t=23733