Jerking and hesitation

[Pardue]

I have an 06 GT with 69,000 miles. The car is all stock except for axle back exhaust and an Airaid intake. When the car is cold it hesitates and jerkes pretty bad. It only does it at light throttle or when letting off the gas cruising. After the car is warmed up it drives fine. I tried cleaning the throttle body and the MAF sensor but it didn't help.

I guess next I will change the spark plugs and see if that helps. Any ideas on what else could be causing this issue? Any help is greatly appreciated.

 

[702GT]

Once it starts hitting 30-40 in Vegas my car does the same thing. I usually start the car and let it idle for a minute then give it a couple slow revs to 3-3.5k/rpm and take off. Seems to help rather than just pulling out of the driveway and going.

 

[Pardue]

I can't really rev my car at 4:30 AM when I leave. My neighbors already hate me.

 

[bmaxwell]

Pretty sure it's your plugs

 

[wa2fst4u]

Mine did the same w/Steeda cold air + SCT. In the mornings pulling out it would buck wildly at part throttle. Warmed up it would run great until it cooled down. Pulling out from a stop sign or light was an adventure when cold.

Got the car tuned and all problems went away...like magic!

 

[Pardue]

Pretty sure it's your plugs

Hopefully it is the plugs. I am going to get a new set of OEM plugs and install them this weekend.

Mine did the same w/Steeda cold air + SCT. In the mornings pulling out it would buck wildly at part throttle. Warmed up it would run great until it cooled down. Pulling out from a stop sign or light was an adventure when cold.

Got the car tuned and all problems went away...like magic!

If the plugs don't fix it I guess I will have to look into getting a tuner. Will the OTS tune work or will I need to have it dyno tuned at a shop?

 

[Brenspeed]

Try this first. With that many miles you could definitely have some buildup on your throttle body or blow by oil sitting behind your throttle body which would give you these issues...

http://www.youtube.com/watch?v=dR4M-UI-wKk&feature=player_embedded

My second guess would be a set of spark plugs...

Hope this helps!

Thanks,
Chandler

 

[Norm Peterson]

When the car is cold it hesitates and jerkes pretty bad. It only does it at light throttle or when letting off the gas cruising.

Do you wait for the idle to drop off the fast idle setting before driving off?

Have you tried the throttle reset procedure?


Norm

 

[Pardue]

Try this first. With that many miles you could definitely have some buildup on your throttle body or blow by oil sitting behind your throttle body which would give you these issues...

http://www.youtube.com/watch?v=dR4M-UI-wKk&feature=player_embedded

My second guess would be a set of spark plugs...

Hope this helps!

Thanks,
Chandler

Thanks Chandler! I actually took the throttle body off and completely cleaned it last week. It made my idle perfect but didn't help the hesitation.

Do you wait for the idle to drop off the fast idle setting before driving off?

Have you tried the throttle reset procedure?


Norm

I let my car warm up atleast 2 minutes before driving always. I have not tried the throttle reset procedure. How does that work?

 

[wa2fst4u]

Ran great during the summer, but now with colder temps it's doing it or just when the car if first started?

BTW.. I tried all of the above - same results. I did put the stock air box back on and removed the tune - the problem went away so I figured it was in the tune. Not sure if you have a tuner (SCT/Diablo) though.

To recap - spark plugs, clean TB, throttle reset procedure and battery disconnect reset all to no avail. I'm sure each situation is different, but putting out my experience - which sounds very similar.

 

[kampendmk]

same problem

I had the same problem two weeks later my battery went out replaced the battery and the car is fine

 

[Pardue]

Ran great during the summer, but now with colder temps it's doing it or just when the car if first started?

BTW.. I tried all of the above - same results. I did put the stock air box back on and removed the tune - the problem went away so I figured it was in the tune. Not sure if you have a tuner (SCT/Diablo) though.

To recap - spark plugs, clean TB, throttle reset procedure and battery disconnect reset all to no avail. I'm sure each situation is different, but putting out my experience - which sounds very similar.

I actually just got the car 3 weeks ago but it does it on 30 degree mornings and 60 degree mornings.

I do not have a tuner. I have not done the throttle reset procedure or battery disconnect reset, just cleaned the throttle body and MAF sensor. I will try the reset procedure if the spark plugs don't help.

 

[NinjaKiwi84]

My throttle is jerky on cold start too. Every car I have ever owned was basically this way, just a big more noticable on the Mustang. Def let the car idle a minute or 2 before pulling off and see if it still does it. It is never a bad thing to let any car warm up a tad before driving off anyway.

 

[Pardue]

My throttle is jerky on cold start too. Every car I have ever owned was basically this way, just a big more noticable on the Mustang. Def let the car idle a minute or 2 before pulling off and see if it still does it. It is never a bad thing to let any car warm up a tad before driving off anyway.

I always let the car idle/warm up ATLEAST 2 minutes or so before I drive away. I like the let the oil circulate and let the idle drop to normal before I drive away.

 

[Blank]

Mine does the same even if i let it warm up for couple minutes. If i just roll out with no throttle its good. How do you reset the throttle response?

 

[06silverbullet]

you guys crack me up, i live in cali and i let my car warm up for atleast 1 minute before i move it at all, not for the sake of drivability but to get the fluids circulated espcially

 

[Norm Peterson]

As soon as it falls off the fast idle, it should be ready to drive. This does not mean that you should go charging off at Interstate-ish speeds, though, so there are situations where a slightly extended warmup has benefit.


Norm

 

[Bodam]

I try not to hesitate when I am jerking

 

[Black_GT]

I try not to hesitate when I am jerking

Damnit! You beat me to it!

 

[Pardue]

Mine does the same even if i let it warm up for couple minutes. If i just roll out with no throttle its good. How do you reset the throttle response?

I need to search around to find out how to do the throttle reset procedure.

I try not to hesitate when I am jerking

I wondered how long it would take for that response. That is funny man!