Acceleration lag from standstill

[NCC1701]

OK, for a few weeks ... at least the past 1,000 miles on the odometer, this has become increasingly apparent.

My car has close to 11K on it. At first, I thought maybe it was my imagination. But, there is no doubt about it now as it has become more and more pronounced over time.

From a stop, press the gas peddle and there is a pronounced lag of a second or more before the acceleration is more than what you'd expect at idle in first gear. I'm lead footed and I'm talking about more than half way to the floor from the get go. I am certain this lag, if it existed, was nowhere near this severe in the past.

I've got the Breathless Performance air filter. Is it possible I need new plugs already? What else could it be? Or, is it possible it's all in my mind that the lag has increased?

[mdfortwoguy]

Is it doing this with the A/C off as well? Has it been more humid since this started happening?

Mine isn't as punchy offline the past few weeks, but I have had the A/C cranked and have been dealing with pretty high humidity aorund here... it is working with about 62 or 63 HP with the A/C on though...

[Padawan]

My guess would be that it's likely a combination of hotter weather (less power being generated overall, and perhaps a slight possibility of some ignition timing being pulled under load) and your mind playing tricks on you.

New plugs couldn't hurt, but I don't think they'd be at the point of causing a performance loss just yet.

[John_H]

Want to try something blasphemous? Try a couple tanks of mid-grade unleaded.

While I wouldn't expect Florida gas to suffer from the same troubles as the stuff in the northwest (flamability too low in premium) the same things that brought the pep back into my BMW roadster might work for your smart as well. By burning a little hotter, if there are deposits forming, they might be encouraged to leave. If the starts are slow - most notably "cold" starts - the increased flammability of the mid-grade might get over that first second of hesitation.

Blaspheme! I know.

[Bum-bling-B]

Wow NCC - I do have a similar problem with Kermit though I have a feeling it might be something else with mine but I need to wait for a code to confirm. JohnH's suggestion is something to try so I won't scream BLASPHEMY!!

[NCC1701]

Originally Posted by mdfortwoguy

Is it doing this with the A/C off as well? Has it been more humid since this started happening?

I don't know about the A/C, it is always on from March through October. But, I will sweat it out experimentally tomorrow. Since it is on most of the year and I've had the car almost a year now, I kinda doubt that is what's going on. Humidity? It's humid enough to drink the air most of the time. Relevant or not, it isn't a new factor any more than the heat is.

Originally Posted by John_H

Want to try something blasphemous? Try a couple tanks of mid-grade unleaded.

While I wouldn't expect Florida gas to suffer from the same troubles as the stuff in the northwest (flamability too low in premium) the same things that brought the pep back into my BMW roadster might work for your smart as well. By burning a little hotter, if there are deposits forming, they might be encouraged to leave.

I thought Techron was supposed to be protecting me from deposits.
Anyway, I follow your thinking, will consider.

Originally Posted by Padawan

My guess would be that it's likely a combination of hotter weather (less power being generated overall, and perhaps a slight possibility of some ignition timing being pulled under load) and your mind playing tricks on you.

Because the intake air is warmer, it has less expansion available (guessing)? I'm not enough a gearhead to know what you mean by "a slight possibility of some ignition timing being pulled under load", but it sounds expensive. And, my imagination has proven expensive on a number of occasions.

[NCC1701]

Originally Posted by Bum-bling-B

Wow NCC - I do have a similar problem with Kermit though I have a feeling it might be something else with mine but I need to wait for a code to confirm. JohnH's suggestion is something to try so I won't scream BLASPHEMY!!

Maybe it is the UFOs from Gulf Breeze? Well, you and I are in the same neck of the woods. Are you talking about an error code you can get from SGII?

[Bum-bling-B]

Originally Posted by NCC1701

Maybe it is the UFOs from Gulf Breeze? Well, you and I are in the same neck of the woods. Are you talking about an error code you can get from SGII?

Yeah - throw a code in the computer on the car. I just turned over 28k this afternoon.

[HGB]

My A/C when on will definitely create a hesitation from a stoplight start. I don't like it one bit either. What's the answer.?

[Padawan]

Originally Posted by NCC1701

Because the intake air is warmer, it has less expansion available (guessing)? I'm not enough a gearhead to know what you mean by "a slight possibility of some ignition timing being pulled under load", but it sounds expensive. And, my imagination has proven expensive on a number of occasions.

It's nowhere near as bad as you're thinking, don't worry.

Warmer air is simply less dense, and therefore contains less oxygen per given volume. This means the computer mixes in less fuel to maintain the proper mixture, and the result is less power being generated by the engine.

As for the ignition timing, higher engine temperatures and higher intake temperatures can increase the likelihood of detonation (otherwise known as knocking, pinging, etc.). When the computer senses detonation, it will retard the ignition timing to prevent it. This has the side effect of reducing engine power output.

And then there's always your imagination...