2005 Mustang 4.0: Do I need a Tune for my Granatelli Throttle Body Upgrade?

[Stangman Jonathan]

I just recently got a good deal on a Granatelli Throttle Body with low miles, actually very little if anything so I picked it up, but now realized I am not sure if I will need a new tune with it.

I know the 4.0s have been very picky in regards to throttle body upgrades, so I wasn't sure. Yet, anything is better than my stock throttle body.

Long story short, I had one replaced within 5,000 miles of owning the car for staying open and the car continue to accelerate after I got off the throttle. Been having this happen again for the last few weeks and rather not deal with it, not sure whats going on but no, it's not the floor mat. I have a heavy duty Mustang floormat and its secured in its track. Dealership had the told me that multiple times, until the mechanic took it for a spin and experienced it himself.

So any idea if I'll need a tune for this or if it can wait until I add other power add-ers?

[GT800]

No you don't

thanks
Dan

[Stangman Jonathan]

perfect, now if others have this same question, they can reference this thread

[PWRBY4D]

maybe you will have a little better throttle response.

[Hotshot]

Don't you have free tunes for life? If so i'd get a new tune cause anything that effect yourr air or fuel will affect the afr, that's always been what I've told people cause its logical after all lol. As for your throttle sticking open, that could be multiple things but hopefully replacing it all together works. I used to hit my oem tb with tb cleaner twice a year to keep it nice and clean, free of oil and dirt. Now the tb cleaner says "not on s/c" cars lol.

[GT800]

A throttle body won't change your air fuel ratio it will just effect the response

thanks
Dan

[Hotshot]

Originally Posted by gt/cs07

A throttle body won't change your air fuel ratio it will just effect the response

thanks
Dan

Even if its bigger?

[GT800]

Still the same amount of air being read by the maf it will just allow it into the intake manifold faster

thanks
Dan

[Stangman Jonathan]

Alright guys I need your help, I want to drive her Saturday but this whistling is driving me nuts. It happens when I step on the throttle even lightly....I assume it's due to the bigger throttle body? If so I have to see if I can get a custom tune from AM for Saturday which may be tough, with such a short time left.


What do you all think? I'll try to get a video later

Well my day just went really bad. Had it sitting here at school waiting for class and it started stalling out, lost throttle response. So now I'm royally screwed. Class til 9 and then I have to get my car started to get it home

P2104

[NASTY03GT]

I would contact GMS. That shouldn't be happening. An updated tune is not required for the TB, but it won't hurt for it will allow the car to learn its idle better, etc. But it won't do anything about the whistling unfortunately.