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RPM problems

Hello, I’m new here. I just bought a 2009 429R Roush mustang supercharged at only 12,000 miles on the car. I was shifting to 4th from 3rd at a higher RPM starting a race and I accidently caught 2nd gear. Check engine light came on and lost power so I came to a slow. No smoke or anything obviously wrong. I took back off and I was in 1st at 3500 RPM, then 2nd gear… then when it reached 2800 RPM I hear crackling noise and loss of power. I shifted and same thing on every gear except 1st gear. Keep in mind this is a super charged car. It drives at 55 or 60 and I can drive around in any gear with zero issues unless i go to 2800 RPM I’m baffled at what the issue is. What do you guys think?

When a fault is detected by the PCM the rev limiter may be reduced to protect the engine. Connect to the PCM and read the fault codes. Why should there be smoke?

You did what is known as the “money shift”

You over revved the engine and bent a valve or 2… at least… and maybe more.

I hope your credit is in good shape, this will be expensive.


That it’s going to cost you more to fix it than I paid for my last car.

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I tested that idea, In 1st I took it to 4500… no issues… it’s only happening in 2,3,4, at 3,000 RPM.

The last person I know that did that with a Mustang grenaded the transmission.

Right after I just rebuilt the turbo engine.


Ok i went to Autozone and had code pulled, cylinder 5 is misfiring… any thoughts from this happening from a hard down shift?

@Mustangman gave you the answer in his first post.


Now you know one of the 3 valves in #5 is bent. I’d suggest running a compression check… I also suggest pulling both heads cause there may be some damage on other cylinders.

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Am I the only one wondering how someone manages to hit 2nd gear when downshifting from 4th to 3rd?


I was in 3rd going to 4th and downshifted to second.

Ah, okay, I misread your initial post.

I might have mistyped it, I’m on a phone

Or why someone that has a limited edition car (only 100 made) is driving it so hard.

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Or why someone that has a limited edition car (only 100 made) is driving it so hard.

It seem’s that some people have more money than sense.

People don’t buy vehicles like this to drive like you are hauling eggs in the trunk.

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Or it could be that someone has enough money to afford a limited edition supercharged car and would rather run it hard on the track than on the street. I don’t know about you, but I’d rather they drive like that on the track than my local highways…

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Because that is what it was made to do…

Limited or not, the car was built to haul @#$, not just to sit and look pretty.


Although it probably does both quite nicely.


Thank you… not sure why people are giving me h3ll… I made a mistake… I’m about to pay for it. I just needed advice from veteran car peeps.