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Rev Limit Cuts Engine at 120 mph

4807 Views 92 Replies 18 Participants Last post by  20focusstdriver17
I was on a road trip in my RS thru desert land. I opened-it-up a few times, and each time the rev limiter cut in at 120 mph. Elevation was about 4,000 ft. I expected to be able to go faster than 120 mph!

Any thoughts?
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My guess is your key is setup as a mykey with a speed limit coded to it
That is what it sounds like.

OP, find a racetrack try again and use the other key to the car. Don't do these runs on public roads.
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I am unclear what you mean by "other key".
You get 2 fobs.

Thats what he is referring to when he says other key
Excactly, in order to make a myKey, an Admin key must be present. There should be two keys to the car, if the limit is a myKey issue like we suspect, the other key should be the admin key.

As far as the speed limits that can be set, I don't recall the full range, but I know on the RS you can set it, I know on the myKey I setup for mine, when my daughter was driving it, was 70MPH, no drift mode and such. 70MPH is the highest speed in my area, but that is over 30 minutes away and not where she was authorized to drive the car.
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I was in 6th gear. As I watched digital speedo I saw the rpms qaapproach redline and the engine c

Vehicle is 100% stock.
Either you don't' know what gear you were in, something is really wrong with your clutch (and you don't know that smell), or the car is not 100% stock (ECU parameters included)
How pathetic ..
You came here saying you have a 100% stock RS, in perfect working order, and it redlines at 120MPH in 6th gear. Something you said is wrong, no way all conditions you have are true. You didn't mention the redline in 6th gear until after several other plausible suggestions. If you don't want to listen to every other owner that knows you have something wrong with your assumption, move on.
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I guess the dealer will have to charge him dyno time just to test since they can't easily legally test that issue any other way.
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I cannot imagine asking the dealer to even investigate this... How do you ask for them to check this out so that you can exceed this 120mph on public roads? 🤨 I would imagine even most track day tracks are not high speed, it is more about acceleration, brake, acceleration, brake, etc.
It would depend on the track. I know at ViR I can get over 120MPH on either straight, should be able on RA too (on "back straight" between turn 7 and 10A), NCCAR I can reach it, but not sure it would be there long enough to really diagnose much of anything. But if you are diagnosing an issue the dyno is a way safer place for testing.
Ok guys I’m not gonna read this whole thread, but OP says he was in 6th and was at redline and only did 120mph. regardless of what key or a valet mode, the car has gearing and logic would dictate either

1. The OP is lying
2. The OP is just wrong
3. His clutch is slipping so bad that it allowed the car to bypass the actual gear ratios
Remember, he didn't say anything about redline at the point that anyone was suggesting a possible key/valet mode issue. Once that was brought to light, those ideas were out the window as there is some mechanical issue (something preventing the engine RPMs from reaching the tires through the expected ratios) or an electrical issue (causing the car to think it's at a higher RPM or the speed is way slower than it actually is).
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Uhm, the OP is an idiot. Reminds me of the stupid f*cks on the honduh forums during The Forum Wars back a decade ago. Well, before I was banned. The title of this thread says “rev limiter” at 120 mph” not some ambiguous rpm, the rev limiter, which is a simple thing to discern. Close the thread and move on.
I'm not sure what you are saying, are you saying that you inferred that he was saying "red line" from "rev limit". I could easily see someone saying it is rev limiting at 120MPH while only at 4,000 rpm unless the car is using the brakes to limit the speed. The car limits engine speed and vehicle speed by limiting the engine RPM (rev limiting).
Ah, to me they are two different methods of limiting revs/speed. The speed limiter does control revs, otherwise it could not control speed. I've had the rev limit feel smooth too after using the over rev zone too long and it was slowing me down to the lower limit before a braking zone.
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