power fading. faulty perception or real possibility?

[adamkiwi]

So I took my little 3 out for a spin around town tonight and I could swear my highway acceleration felt really weak after a while.

After about 15 or 20 miles @ 70 plus (with a couple of sprints up to 95) my 5th and 6th gears felt lacking under hard acceleration.

I pulled off MOPAC and just drove the access road for a little bit... I putted along for about 2 or 3 minutes to cool down the turbo (not that it should have been particulary hot...). After a few lights, I hit it in 2nd, 3rd and 4th - each up to about 5600 revs...(i'm not going for a track time here).

Now, this is my first turbo car. But I've ridden in a few and have learned a little bit about turbine/fluid dynamics.

The turbo, tonight, seemed to have a noticeable "lag" - more so than I've noticed before. And the power produced through the "band" seemed to waver slightly at a few points during each pull.

Can this be? I've got 1500 Miles on my speed3 and have been relatively restrained. I l always let the turbine cool down before shutting her down. I don't ever get on it while it's still "cold".

It is humid tonight @ 86 degrees here in Austin TX. But cooler than it is in the daytime.

Is it me? Or is it my imagination? or could there be something to check?

 

[VermZ06]

You're probably just getting used to the speed finally. When I went from MSP to MS3 the speed felt unbelieveable and now I'm getting used to the MS3's mannorisms so it doesn't surprise me that much anymore. It's not that it's not as strong you're probably just getting used to the car's abilities.

 

[controlo]

i agree. sometimes the car WILL be faster than other times though.

 

[clos561]

ur definielty jsut used to the car now..the first time i drove the car it was amazing and i felt like i was in a rocket or something now with cai and almost a year of driving the experience is not near the same..u get used to it .i guess u can look at it as motivation to keep modding and getting more power so u never get "used" to it

 

[whitey4311]

Get next to another car and take off then it wont feel so slow any more. I am used to the power and keep thinking what I want next but after kicking my friends ass who has an Evo I am all tickled again and love my MS3.

DOnt push the car hard with normal driving and every now and then when you open it up you will really be happy with the power.

 

[Speedy3]

Does you car ever seem to stutter on acceleration?

 

[fourthmeal]

Off the top of my head:

Leaking BOV
Bad ECU flash
Poor Gas Quality
Stock airbox (if so, cut the airbox or install CAI)

Could be a few other things, but those would be the first I'd check. I'd also double check the connection to the battery.

 

[subparpunk03]

If you think that something might be wrong with your internals there are a few things you can check.

You can buy a $20 compression tester (or have a shop do it). This will tell you if something is very wrong with the pistons or piston rings or anything else inside the engine. This would be an indicator of a very serious problem and you would def be able to get warranty repairs.

Check the spark plugs, if they look really really dirty you have a problem... take it to dealership.

I would also reccomend checking the boost to make sure you aren't leaking. You can get a basic pressure gauge and hook it up if you don't wanna spend the money on a permanent install gauge. Autozone should be able to help you do this.

If it was a serious problem I think you would definately notice it more. Like most people have said, you are probably getting used to the power. If you are paranoid about stuff like I am though these are a few easy checks you can do to make sure you're tip-top.

Oh also only use premium gas, that does make a very big difference

 

[subparpunk03]

Ah one other thing. I'm not 100% sure if the mazda ECU is like this, so if someone can confirm this that would be wonderful, but this is just wild speculation at this point:

In my Corolla XRS the ECU would "re-tune" itself based on certain driving parameters... for instance, if I was doing highway driving or stop and go traffic or some other sort of slow, non-performance oriented driving, the ecu would reconfigure itself to adapt to those driving situations and as a result wouldn't be as responsive or fun if I started driving harder in closed loop mode (meaning not going Wide Open Throttle). It would seem like the car had been restricted. However, when running in open loop (WOT, above 4k rpms or so) the car would be back to normal.

Point is, it is possible the mazda ecu is just responding to your driving style at that moment, drive it hard for a few minutes and it will re-adjust itself again. You could also try manually resetting the ECU, not sure if there's a better way to do it (I've had my 3 a week) but you can disconnect the battery cable for a minute or two then hook it back up and everything should reset.

 

[Speedy3]

Does you car ever seem to stutter on acceleration?

If you do check the spark plugs like subarpunk mentions, check all of them and not just the #1 (you gotta remove the TMIC for 2-4). Make sure and check carefully for cracks. I had similar symptoms and the dealer only checked the #1 spark plug and refused to go further without a cel. I removed all of them a few months later and found the #2 and #4 to be cracked. It started at about 2500 miles or so.
"http://www.mazdas247.com/forum/showthread.php?t=123656333&highlight=stutter"

http://www.mazdas247.com/forum/showthread.php?t=123656333&highlight=stutter

 

[lokalmotive]

6th gear will seem to have a little more lag considering it is a crusing gear and not an acceleration gear. Going 70 mph in 6th gear and punching it won't be the same as 4th or 5th gear. Try it from those and see if it has a little more oomph to it. But then again it could be some of these other things ppl are saying. My guess is you're just getting used it and trying to accelerate to quickly from the wrong gear.

 

[adamkiwi]

Thanks All -

My drive to and from work today revealed that my perception was probably just off last night...

Acceleration was spirited in 3rd through 5th all the way across the powerband...

Somebody mentioned gas though... Does 89 or 91 octane really decrease performance significantly or risk damaging the engine?

Thanks Again!

Adam

 

[clos561]

Thanks All -

My drive to and from work today revealed that my perception was probably just off last night...

Acceleration was spirited in 3rd through 5th all the way across the powerband...

Somebody mentioned gas though... Does 89 or 91 octane really decrease performance significantly or risk damaging the engine?

Thanks Again!

Adam

yes higher octane is cleaner burn and the car can perform better and faster

 

[LENNY127]

it's in your head man, I feel that too ...there is a diagnosis for it. it is called "need for speed", I have run from a 13 second Nova , 12 sec Vega and an almost flat ten Luv truck and after a few weeks or months you just get used to it but you swear you lost power. I still catch myself from time to time checking acceleration on the g-tech just to see because this car is so inconsistent throughout the gears and rpm band.

 

[Betelgeuse]

Ah one other thing. I'm not 100% sure if the mazda ECU is like this, so if someone can confirm this that would be wonderful, but this is just wild speculation at this point:

In my Corolla XRS the ECU would "re-tune" itself based on certain driving parameters... for instance, if I was doing highway driving or stop and go traffic or some other sort of slow, non-performance oriented driving, the ecu would reconfigure itself to adapt to those driving situations and as a result wouldn't be as responsive or fun if I started driving harder in closed loop mode (meaning not going Wide Open Throttle). It would seem like the car had been restricted. However, when running in open loop (WOT, above 4k rpms or so) the car would be back to normal.

Point is, it is possible the mazda ecu is just responding to your driving style at that moment, drive it hard for a few minutes and it will re-adjust itself again. You could also try manually resetting the ECU, not sure if there's a better way to do it (I've had my 3 a week) but you can disconnect the battery cable for a minute or two then hook it back up and everything should reset.

+1

I have noticed this as well. If I drive slowly all day and all of a sudden step on it, it will respond but not like if I was driving it spiritedly like I usually do. I'm pretty sure we have an adaptive ECU as well.

 

[dichiee]

experienced this the other day... i hope its just in my head by i noticed that I was flooring on 3rd and 4th i think and it won't pass 4K RPM I downshifted and it woke up a bit. Is it maybe I've been driving the car less than 4K rpm for the first 500 miles?

 

[gru]

You're going to have to explain this better.

You're saying in 3rd and 4th gear your car won't go past 4k?! Or the power after 4k is not good? I don't understand.

 

[dichiee]

You're going to have to explain this better.

You're saying in 3rd and 4th gear your car won't go past 4k?! Or the power after 4k is not good? I don't understand.

Yup I was flooring the gas but the RPM was really going slow from 3 to 4 usually it's fast but for some reason car wasn't really pulling but after slowing down and down shifting the response of the car went back

 

[gru]

So it was a little hic-up? After you slowed down and downshifted and went from 3rd to 4th again it was ok? Or this is a constant problem with 4th gear?

 

[dichiee]

ya it was ok again after that. ya i guess it was a hic-up but I'll keep an eye on it if it happens again hopefully it won't