Early rev limiter 3k
02-10-2019, 05:12 PM
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Early rev limiter 3k Hey guys, I just picked up my first f-body, 98 Z28 M6. I noticed it doesn't go past 3k rpms, it's like it's hitting an early rev limiter. Also the ARS and brake light are illuminated. I'm wondering if the gears have been changed out. Any ideas before I pull off the differential cover.
02-11-2019, 01:45 PM
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Does this only happen in gear/under load (when accelerating), or does it also get stuck at 3k rpm during a free rev in neutral? If only the former, can you mechanically force it above 3k by downshifting to a lower gear at speed?
Are you seeing an SES light? I'd check for any stored/pending codes. Does it have any other driveability issues (such as idle problems, overheating, trouble starting, etc.)? An exhaust blockage is certainly a possibility, but this could also be due to fuel or spark issues depending on other symptoms.
Are you seeing an SES light? I'd check for any stored/pending codes. Does it have any other driveability issues (such as idle problems, overheating, trouble starting, etc.)? An exhaust blockage is certainly a possibility, but this could also be due to fuel or spark issues depending on other symptoms.
02-11-2019, 03:52 PM
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So I just free revved in neutral and it doesn't go past 3000rpms but the engine sounds like it's revving up around 5000-6000. I just had the entire exhaust replaced due to exhaust leaks and it didn't change anything. No check engine light and no pending codes, no driveability issues whatsoever. Could it have a tune with a rev limiter or is my tach just way off? It has power all the way up 3000 Rpms under WOT, I feel like I can't the most out of each gear without it needing to upshift. I'm stumped guys.
02-11-2019, 07:45 PM
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I can't think of any reason someone would limit the engine speed in the computer. If you think the gauge is off, do you have a little scanner you can hook up? I use a little blue tooth OBD-II dongle I got on Amazon with the pro Torque app for android, and that would give accurate RPM information (among other things.)
What happens when it goes to 3,000 RPM, does it bounce like it hits a limiter? Or does it sound like it starts misfiring? Could you get a video?
What happens when it goes to 3,000 RPM, does it bounce like it hits a limiter? Or does it sound like it starts misfiring? Could you get a video?
02-27-2019, 11:15 PM
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Update!!! I purchased obd2 Bluetooth adapter and installed torque pro app like you suggested and found the RPMs are actually going past 3000 so it's the tach that's wayyy off. I revved all way to 4900 in neutral just for testing purposes. At 65mph in 5th gear my RPMs are at 2600, I did the calculator and looks like maybe I have 4.10 gears, do you guys agree?. Also running C6 wheels 245/40/18; rear: 285/35/19) . Thank you in advance