Help: Jerkyness/uneven power at Idle

[PMB]

2006 GT, is automatic, and has ~53,000km. Just had some service done last week

Anyways, I thought this was associated just with cold weather and a higher revving engine while cold. The problem is that while in first gear, if I let the brake off, without pressing the gas, the power delivery seems very jerky until the car starts rolling a bit faster.

The problem is most apparent when just rolling in traffic with the brake applied. Seems like the engine is trying to gain revs to prevent stalling. The engine has never stalled. When in Park or Neutral the idle feels smooth, but sometimes gains a couple hundred revs after dropping a bit... like the engine is testing to see if it can run at a lower rev, but something tells it to speed up a bit.

Sometimes when the engine is warm, the engine idles at around 500rpm, sometimes it seems higher like 700-800rpm.

I've read that there is a flash for some computer to adjust shift points? I don't think I have this because shifting from 1->2 is pretty rough. Also, when slowing down (gliding) just below 60km/h the automatic shift from 5->4 is not too smooth either.

I don't know if any of this is actually a problem, or if I'm just being very anal. Let me know

[m3zoomzoom]

if it's only when its shifting gears... have you checked your transmission fluid? i know our cars transmission fluid seems to get dirtier and needs to be changed more often than most other new cars...

if its also when its not shifting gears maybe its dirty injectors or bad fuel? try some injector cleaner or seafoam your engine... might help a bit...

[M3-ZOOM]

i think im experiencing the same thing, but mine goes away when my engine is warm. I am pretty sure its just the transmission isnt warm enough, hence the jerkyness from gear 1 to 2

[urbanjoe]

I have the same problem from 1st gear to 2nd gear,but once it warms up it goes away. To be on thesafe side though change your transmission fluid as stated below.

[CanSpeed 3]

Do you havw any mods? After doing an intake/exhaust mine does this the odd time when its cold, but stops once its warm. Im also standard.

[PMB]

Do you havw any mods? After doing an intake/exhaust mine does this the odd time when its cold, but stops once its warm. Im also standard.

No mods.

As to all the other replies. I know the shift from 1-->2 is an issue and I have it.

Specifically, I'm just asking about and issue, where when the engine is cold and the revs are higher, power delievery in 1st gear (and only first gear) seems very jerky, which is only noticeable when the brake is applied but the car is rolling forward under power... like when you creep forward at a stop or in traffic.

I haven't had a chance to poke around under the hood yet, but if I have a chance and deside to check the transmission oil, I'll let you know if it looks dirty or burnt or anything. I do drive the car quite hard.

[PMB]

Took it to the dealer,

Here is a list of the work done:

Complaint:Check for Jerking at lights/stop when creeping forward
Cause: Road tested veicle - checked for codes none in system
Correction: Reset keep alive memory and reroad test ok

Complaint: Check for hard shifting between first and second and downshifting from fifth to fourth
Cause: Check for codes none stored in system checked for PCM update. 1 available
Correcton: Performed PCM and TCM update for hard shift F0010XFX 0.3

I drove the car again this morning, and when it's cold, it's still jerking while creeping forward at a stops. I had the radio off, and to me it sounds like there is a fluid gushing or sloshing sound when accelerating.

[TheMAN]

they need to clean the throttle body... it's related to the stalling issue
a flash update would've helped had they cleaned the throttle body also!

[sas]

there is a fluid gushing or sloshing sound when accelerating.
I have no doubts in professionalism of dealer but had you checked the coolant level?

[vnon3luv]

It could be the Purge Soloniod i got my replaced from Toronto Mazda from Joe and it fixed my problem. I had a similar issue but my stalled at the traffic light while it's cold outside. The engine feels like it wants to rev higher but can't than it stalls. While driving it's no problem only at the stop sign.