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My car is fairly new and not that well documented online (it's a new model from late 2015)

For safety, how do I know if my car has a REV-limiter without testing it and letting it go up the red line RPMs? Is there a visible hardware or a sticker somewhere that would denote this?

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    Research? Every car is going to be different. – Pᴀᴜʟsᴛᴇʀ2 Feb 18 '16 at 23:59
  • Sorry, let me rephrase the question Paulster. – Jomar Sevillejo Feb 19 '16 at 0:03
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    Cars from the 90s had fuel cutoff so it's safe to assume that all cars from that point on have fuel cutoff. Honestly though unless it's documented somewhere you'd have to dump the ECU ROM and decode it. – Ben Feb 19 '16 at 0:17
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    @JomarSevillejo Yes I'd even assume any fuel injected car has fuel cutoff. – Ben Feb 19 '16 at 0:21
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    @JomarSevillejo - As stated in my comment below ... It is a very bad assumption to believe all fuel injected cars have a rev limiter in them. – Pᴀᴜʟsᴛᴇʀ2 Feb 19 '16 at 1:23
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Rev limiter is a bit of a misnomer since maximum engine RPM is a function of airflow. However there are such things as fuel and spark cut off which will disable either injectors or coil packs as a result of going over a predefined RPM (this also happens on deceleration).

Doing a little research I found a patent that dates back to 1980 (https://www.google.com/patents/US4336778).

So all in all it's safe to assume that any fuel injected engine has some kind of "rev limiter".

  • I really think it's a poor assumption and one I'd not believe is there. The only engine I know for sure has a limiter (or fuel/spark cutout) is the MX5 Miata. That's only because I tacked one up there once. There may be something in the PCM which does this automatically, but it's bad to assume this is there in all fuel injected vehicles. Plus, the link you provided is for fuel cutoff to save catalytic converters in the case of misfire, not to prevent over revving. – Pᴀᴜʟsᴛᴇʀ2 Feb 19 '16 at 1:18
  • @paulster2 Pretty sure all OBD2 GMs have fuel cutoff (2000 + for sure). I know Mitsubishi uses one as well as Subaru. Nissan for sure as early as 89. – Ben Feb 19 '16 at 1:28
  • I understand where you are coming from, but for the most part it's still an assumption. Is there a way to know for sure any engine has a fuel/spark cutoff? Without specifically researching any engine/vehicle you really don't know for sure. You'll want to double check the patent you have posted ... it's not for over revving, as I stated before. – Pᴀᴜʟsᴛᴇʀ2 Feb 19 '16 at 1:46
  • @paulster2 you're right there's no way you would know without researching or testing yourself. – Ben Feb 19 '16 at 2:31
  • @ben Could it be possible for him to sue you if he blows his engine up? – HandyHowie Feb 19 '16 at 8:29

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