[06MustangGT]

I was wondering If anyone was having this sort of problem with any of their S197 Mustangs. I have a 2006 Mustang GT with a 5 speed. When I get past 4500 RPM'S the car just seems to sputter like there is not enough spark or airflow. This is not that bad with the stock tune. Now I know Ford's new Throttle by wire design could be the cause of this. I had the car checked out at the ford dealership and it checked out ok. So I ordered a C and L Cold Air Intake with 87, 91, 93 OCT tunes from Brenspeed. I thought that this would solve this problem with the throttle not opening up instantly. I was wrong. The car runs awesome under 4500 RPM's, but sputters at the high RPM's. I'm taking the car back to Ford tomorrow, but I don't know If they will get to look at it since they are only going to have half the Tech's there and because of the Holidays. I don't think It Is the tunes from Brenspeed since it was on the stock tune but I thought this was due the throttle by wire. I tried looking at the TSB's but I could only find the hesitation after a long cruise. Could it be a bad throttle body? This is driving me crazy, and this is the last thing I want after being out in Iraq for 15 months. Again I love the cars reponse from the tunes from Brenspeed, but the sputtering???????

[Luis_GT]

My car has only sputtered twice... and it was from dropping a gear to go up a hill or pass someone after cruising for a while.

as far as sputtering above 4500, no, last time I did a burnout I kept it @ 5600 RPM for 15 secs and it never sputtered.

[interceptor]

Sounds like your fuel pump may be losing pressure. I lost mine totally at about 4500 miles.

[06GTMustang89]

haven't had a problem with my brenspeed tune at all....interceptor makes a valid point though

[06RedfireGT]

Mine has never done anything abnormal. Ever. No groaning, sputtering, hesitation, nothing. I guess I got lucky.

[06MustangGT]

Thanks for the replies once again. Brenspeed has awesome tunes and I would recommend them to everyone, I just wanted to let everyone know that. Man what a difference the 87 OCT tune made, just starting the car up aftr downloading the tune!!! Im running the 91 OCT tune now that Im In Arizona. I can't wat to run the 93 OCT tune.

[06GTMustang89]

the 93 is amazing bro!!

[06MustangGT]

06Mustang89

What are the 4.10's like? I have 3.55's in mine right now but I am curious how the cars drives with the 93OCT tune and the 4.10's. Right now the mods that I have done are the Underdrive Pullies, C and L CAI with Brenspeed 87, 91, 93 OCT tunes, and Corsa Axle backs. The Corsa's sound .
I can't wait for the 93OCT but I am enjoying my vacation right now from the Army. I really love this forum alot and the TSB section has helped alot.

Keven

[deadbird]

Get new spark plugs. That is what happens when they are going bad. Usually by bad fuel or fuel additives. Does it ever idol rough when first started or have trouble starting?

[06MustangGT]

No It has no problem Idling or starting just problems when I punch the gas or when I am past 4500 RPM'S. and It sucks because thats where the 91 OCT tune is so great and I bet the 93 OCT tune is also.

[deadbird]

Alot of the times if you ride in the High rpms in these cars alot the spark plugs like to go out quick. I put new ones in about evey 5000 miles. Does this happen under Full Throttle or just cruz. You have to pay attention to see if it does it in the cruz. Or both. And it starts as soon as you go in the the 4500 to 5500 zone of the spark adjustment? It cant hurt to get spark plugs. Get the HT2s for a naturally aspirated car. They should fix the problem and give you better gas milage.

[06MustangGT]

Thanks Deadbird I will give that a try. How much are the new spark plugs?

[JAY'SRED02]

Mine cuts out sometimes after I've been on the interstate for a while and stop when I go to take off again it cuts out for just a second then picks back up again. I think theres a tsb on this but it only occurs maybe once a month.

[deadbird]

Originally Posted by 06MustangGT Thanks Deadbird I will give that a try. How much are the new spark plugs?

Your looking at around $110 sadly. But that is because they are a one of a kind design and only motorcraft and autolite make them at the moment.

[deadbird]

Originally Posted by JAY'SRED02 Mine cuts out sometimes after I've been on the interstate for a while and stop when I go to take off again it cuts out for just a second then picks back up again. I think theres a tsb on this but it only occurs maybe once a month.

There is a TSB but it is for the fuel system. At cruize it causes bubbles and when you stop it settels and goes through the pump. Forgot what the fix is.