RPM drops on 6th gear while accelerating?

[Peedro]

I’m not sure if this is normal but while I’m on the freeway on 6th gear cruising at lets say 65-70,I want to pass another car going the same speed so I step on the gas and as the RPM rise, car accelerates but I see a constant RPM drop then a climb. Now the car’s speed does rise but I’ve never seen small drops like that specially if I’m not shifting gears. Does anyone know if it is normal? Or if something’s wrong I have no idea what it is.. Thanks!

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[turbo lover]

Try to record a video. Clutch slipping maybe?

 

[Deezy]

5th and 6th gears are not intended for quick acceleration.
Your best bet is to drop down to 4th.

 

[Deezy]

Also there is a factory power drop at around 6k RPMs. This can be corrected with KTuner.

 

[Peedro]

Try to record a video. Clutch slipping maybe?

Might be a dumb question but it could still slip even though I’m not shifting gears? And I’ll try to record it today or tomorrow

 

[Peedro]

Also there is a factory power drop at around 6k RPMs. This can be corrected with KTuner.

I have the flashpro but I wasn’t sure if that drop is normal if I push it on 6th gear it kind of worried me when I see the drops

 

[turbo lover]

Might be a dumb question but it could still slip even though I’m not shifting gears? And I’ll try to record it today or tomorrow

Yes, if the clutch is worn then it will slip when you try to put a lot of torque through it. RPMs will surge up when you step on the accelerator, then drop back down when you release it.

 

[Deezy]

I doubt your pulling that much torque in 6th.
In 3rd or 4th gear, get up to around 4K RPMs and floor it. If your clutch is slipping your RPMs will not steadily climb.

 

[alias Igme]

Seems quite strange for rpm to go down while it speeds up within the same gear. If the clutch slips, you will usually see the opposite (sudden rise in rpm but not gaining any additional pull).
Maybe it was slipping the whole time in 6th already and the one you noticed is when it actually engaged.

You are not in a CVT, right?

 

[Peedro]

Seems quite strange for rpm to go down while it speeds up within the same gear. If the clutch slips, you will usually see the opposite (sudden rise in rpm but not gaining any additional pull).
Maybe it was slipping the whole time in 6th already and the one you noticed is when it actually engaged.

You are not in a CVT, right?

Right it’s a manual transmission I’ll post a video of it right now

 

[REBELXSi]

Wouldn't a clutch slip cause a RISE in RPM?

 

[Gruber]

.....so I step on the gas and as the RPM rise, car accelerates but I see a constant RPM drop then a climb. Now the car’s speed does rise but I’ve never seen small drops like that specially if I’m not shifting gears.

You would need to describe it more clearly. What exactly happens to the rpm and car speed after you step on the gas.

Generally oscillations of speed and rpm may happen if the torque produced by the engine drops as the rpm increase to the level below the torque needed to keep the speed. The rpm then slows down under load. As it slows down it regains its torque, so it can now accelerate again until the torque drops, and then the cycle repeats.

Don't lug your engine by flooring the gas at low rpm.
https://www.roadandtrack.com/car-culture/videos/a30431/lugging-bad-for-engine/

 

[crxFITcivicBOY]

You would need to describe it more clearly. What exactly happens to the rpm and car speed after you step on the gas.

Generally oscillations of speed and rpm may happen if the torque produced by the engine drops as the rpm increase to the level below the torque needed to keep the speed. The rpm then slows down under load. As it slows down it regains its torque, so it can now accelerate again until the torque drops, and then the cycle repeats.

Don't lug your engine by flooring the gas at low rpm.
https://www.roadandtrack.com/car-culture/videos/a30431/lugging-bad-for-engine/

Just to clarify for myself on my 6MT... if I’m going say 60mph and in 5th and want to get to 70mph and I’m in no rush, is it okay to put a little throttle to get up to speed then upshift to 6th, or do I still need to drop to 4th. My feeling is if I’m applying only a little throttle it’s no issue, since I’d be sitting at 2.5k rpm anyways... so I’m not lugging or putting to much torque at low rpm in 5th or 6th to cause slipping. Is this general consensus??

To the OP, I’d always downshift to do passing. I’m so OCD that I’m paranoid to even speed up at all when I’m 5th/6th lol (as my above comment).

 

[alias Igme]

for the civic, which RPM is considered low? The normal driving RPM in drive-D (CVT) is already lower than in my other car (i.e around 2k rpm).

 

[tinyman392]

for the civic, which RPM is considered low? The normal driving RPM in drive-D (CVT) is already lower than in my other car (i.e around 2k rpm).

At cruising speeds, it's normal for a transmission to be at lower RPMs. With an automatic, it will prevent you from lugging the engine because if you give it enough throttle input, it will downshift itself. Once you hit a cruising speed and hold steady, the car will shift into the safest, highest gear it can to optimize fuel efficiency.

As for what's considered low, it depends on how much gas you're actually giving it. If you're accelerating at a rate of like ½ MPH per second with a <20% throttle input and sitting at 1500 RPM, it might not be lugging the engine. But if you're flooring it at 1500RPM, you're most likely lugging the engine.

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