bucking when cold

mine was doing the same thing, had my buddy retune it and it went away(original tune was about 8 months ago)

Any error codes?
If not, then reflash the tune.
If no good, then reinstall stock air intake and stock tune. If the problem goes away, then the aftermarket tune may be corrupt. If the problem remains with the stock setup, then the coolant temperature sensor may be bad.
Also, clean off the MAF sensor and the throttle body with some MAF/TB cleaner.

Let the car warm up....

with these cars...you really have to let it warm up nice and good...get that oil circulating around and give it time to lube the cams ect...also, i dont think people realize that you also have to let the tranny fluids warm up too, cause even though the motor is warming up, the tranny oil is barely moving around even it your in neutral. so let the moror warm, then take off nice and slow and let that tranny get some oil on its parts! =) happy driving

jerzeykilla said:

with these cars...you really have to let it warm up nice and good...get that oil circulating around and give it time to lube the cams ect...also, i dont think people realize that you also have to let the tranny fluids warm up too, cause even though the motor is warming up, the tranny oil is barely moving around even it your in neutral. so let the moror warm, then take off nice and slow and let that tranny get some oil on its parts! =) happy driving

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so don't get in it and hammer on it like i do then?

blacksheep06 said:

I don't think I should have to let the car warm up for 5 mins just to avoid getting my head banged into the windshield.

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You're exactly right. It doesn't need 5 minutes, or even 1 minute, to warm up. My S197 performs without any problems after only a 15-20 sec. idling period in the dead of winter with temps in the single digits.
Something is definitely amiss with your car.

I would never just hop in my car and start driving unless it warmed up for at least 5 min... living in NY - it can get real cold

I had this same problem. I'm not sure this will work for you, but cleaning the throttle body seemed to make the bucking problem go away for me.

Even in the summer months I never start and go. Try and allow time for the oil to reach the top of the engine and during the winter months I never let the RPMs go over 3k until the gauges tell me I'm at full operating temperature.

Cleaning the MAF and throttle body as suggested certainly couldn't hurt and may eliminate most if not all the problem... it’s worth a try.

Mine does same thing when I put CAI in and tune, I'm waiting for a Dyno in NY to free up and see whats going on.

Idling is bad for an engine.
This is because the engine is not running under a load, which results in incomplete combustion of the fuel, and the fuel in turn condenses on the cylinder walls. This not only causes extra wear of the cylinder walls(because the fuel washes the lubricating oil off the walls), but it also results in unburned fuel flowing down the walls and contaminating the oil in the crankcase. Other byproducts of incomplete combustion also find their way into the crankcase oil as well, including water, acids, and carbon particles. And these engine damaging conditions are worse during the engine warm up period when the engine is fed a richer than normal idle fuel mixture in order to prevent it from stalling. Idling also drops the temperature of the spark plugs, leading to dirty plugs, which can increase fuel consumption.
The best way to minimize this contamination and resultant engine damage is to warm the engine as quickly as is reasonably possible. And that means driving the car, which places a load on the engine and causes it to generate more heat. 15-30 sec. of engine idling is sufficient to get the oil pressure up and flowing to the critical engine areas, unless the temps drop to around 0 F. Then, idling for a minute or so is recommended. If one lives in a location where the temperature frequently dips way below 0 F, then an engine oil heater should be installed.
Finally, and even more important than the above, is to drive conservatively and stay out of the loud pedal until the engine is fully warmed up.

Idling is bad for the exhaust system.
Water vapor that's produced during combustion forms into water droplets that are deposited inside a cold exhaust system. The longer a cold engine runs at idle, the longer it takes the exhaust system to warm up, and thus more water will be deposited inside the exhaust system causing it to rust quicker.

Idling is bad for the environment.
Long periods of cold engine idling causes the engine to produce a lot more pollutants, because it takes the catalytic converters longer to reach their normal operating temperature when they work much more efficiently.

this may or may not help but there is a TSB (Technical Sevice bulletin) out on the "bucking "problem. This is not necessarily related to the cold but it sounds like it does the same thing >>

youre on the highway at speed, for some time. maybe hundred miles or so. you get off turn the car off, get back in (like at a rest stop - mine did it all the time) then try to get up to speed to merge onto the highway again, the car bucks and jerks your a** all over the place >>

It has to do with the "drive-by-wire" setup - computer etc.. it adapts to your driving style I.E. constant throttle for 100 miles - then it can't handle the weird inputs, i.e. gunning it etc.. so it bucks - Ford is aware of it im sure if you check the sites you can find a TSB on it.

I had mine fixed while under warranty. IF you know of a TSB or a TSB related problem and complain, they will fix it. If not you are up the creek after warranty.

Im am relatively sure its in the computer/ programming or the computer. - that may also be why no error codes show because according to 2005/2006 setup, nothing is wrong - when it really is....

horspowr said:

I had mine fixed while under warranty.

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What was fixed?

horspowr said:

youre on the highway at speed, for some time. maybe hundred miles or so. you get off turn the car off, get back in (like at a rest stop - mine did it all the time) then try to get up to speed to merge onto the highway again, the car bucks and jerks your a** all over the place >>

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That is a fuel pump problem.The pump gets bubbles around the pickup sock and sucks in air causing the engine to "starve" and it wont set a code.