Bucking on light throttle in 1st gear when cold

[Gabe]

Both cars, my Whippled '13 GT and my girlfriend's '13-TVS-equipped '08 GT500, do this, they both buck on light accel when cold, and only in 1st gear.
- Cars were tuned by different tuners, the Shelby done by a local tuner, my car done by JDM via an email tune.
- Both cars use the same intake, a JLT 123mm CAI and that's the only thing in common.
- Different engines, different transmissions, different throttle bodies, different fuel pumps, different type of driveshaft, different clutches, different everything except the CAI, which makes me think it's the JLT CAI, possibly causing turbulence and messing up the MAF signal.

Anybody else notice this?

As soon as the engine warms up a bit, problem goes away.

 

[TenSpeed]

I have this issue!!! Non whippled absolutely stock minus axle backs. Bucks like crazy sometimes.

 

[JUSTA3V]

Mine has done it since day one.... With an aftermarket tune

 

[07TGGT]

My 13 did this as well. Stock and tuned.

 

[pics06gtstang]

Y'all need to move to florida , that cold ass shit will curl your cars
but hole like it curls y'alls , LOL .
what is cold up there -12 , LOL .

 

[JUSTA3V]

I prefer it here, less hurricanes n shit

 

[KatoS197]

Mine did it today actually. One of the few times I cranked it and went without warming up to operating temp. Hell, it was only like 50 degrees?

 

[i am ryan]

Cleaning the throttle body and intake filter cleared that up for me instantly. Noticeably different on the first drive.

 

[Gabe]

Well, the GF's car didn't start doing it until the last round of mods ('13 TVS, '13 injectors, and of course the 123mm JLT), so that's why I kinda started blaming the JLT.
A quick Google search and I found others that were blaming their JLT intakes, but those threads were older and on other forums.

My car started doing it last year and only on cold wet mornings, at least that's when I started noticing it.


Kinda good (I guess) to see that even stock cars are doing it, even though it kinda sucks that it's happening at all.

Guess I'll try cleaning my car's TB, even though I cleaned the Shelby's during the TVS install and the problem's still happening.

 

[loots06]

Mine does that at times

 

[fdjizm]

I would say it's normal and let your car warm up for at least 30 seconds.
Happens to me all the time, just let it warm up.

 

[Gabe]

I let it warm up a couple minutes this morning while I moved my girlfriend's son's Mach1 so I could pull out of the garage and it still bucked although not as bad as it does it on cold rainy days.

On a side note, just moving the Mach over a bit reminded me how much fun that car is too

 

[KatoS197]

Right? I didn't think it would happen, but I find myself missing my 2V and '95 5.0 from time to time. They all have their charms. :')

 

[07 Boss]

You all just need to let your car warm up a bit. Used to be standard practice to let the motor warm up before driving off, but I'm an old fart. I don't start driving until I see the temp needle move. Sometimes that's just a few seconds and sometimes it can be a few minutes.

 

[Sactown]

The car is probably running too rich on cold start, I would have the tuner lean it out a little. In the mean time, you can clean the MAF and O2 senors to see if that helps.

 

[StangPhD]

I would guess they are going lean on tip in. The cold start fuel tables likely need to be adjusted.

 

[eighty6gt]

You can muck around with fuel tables, or you can just wait a second. These cars with blowers, especially aftermarket, are a little cold blooded. Every tune I've ever had has been a bit grumpy when the engine was stone cold if I fire the car up and just start driving, especially when it's down at 30-50 degrees.

 

[nbk13nw]

Same here on cold starts. No wait causes some bucking and sputtering. If I wait until the idle drops, only about 30 seconds, it runs fine. So start drive and buck. Or start wait and run smooth. Lol

 

[Sky Render]

I don't move my car after a cold start until the revs drop down to "regular" idle.

 

[GallopingFord]

Haven't had this issue, but among JLT things I usually complain about them regardless. Lol