Manual Transmission Scary problem!

KrnAndy

So today getting onto a highway, steadily going up the revs in 1st gear (ramp had lights on) the car SUDDENLY did a HARD jerk in the transmission pulling me back, then jerks forward again, within a couple seconds within each other, it happened about 4 times. Felt as if the gear quickly popped out and in or something ( I wouldn't know what it feels like tbh, first manual, shifter stayed in first.) would anyone be able to help me? I don't have warranty as it's 80k miles and thought someone might have insight on what it could be.

Additional notes:
Revs jumped from 3k to 5k then back down (with a VERY aggressive jerk back and forth), it was NOT limp mode, as I've experienced limp mode before. (revs bouncing off)

nis350

likely problems with the clutch. Something caused it to slip and reengage which resulted in the sudden back and forth movement and fluctuation in the rpm..

lhinojos

It being your first manual, It sounds like you let off, and in turn your foot was pressed on the gas pedal pulling you back, and then from that your foot suddenly came off of the gas, so then you had that hard jerk again. First gear is pretty sensitive because It's a really short gear.

If your car is still running fine after that, I think its safe to say there's no mechanical issues here.

Don't suddenly let off the throttle at high RPMs in a low gear unless your taking it out of gear in the process. With more time driving, you'll have better control of the throttle preventing situations like this.

KrnAndy

no.. lol.. I have been driving this car for a couple months now, driving stick isn't hard, and no the hard JERK was not in relation to my gas pedal. regardless if i pressed on it or not, it WAS a problem with the transmission, not sure what though.. but felt as if the gears were slamming into each other or something...

imagine bouncing off a rev limiter at 4k rpm then it shoots down to 2k then back to 4k, but at the same time when it bounces it feels like a sudden jolt and you hear a thud in the transmission every jolt, all while i was accelerating and it happened randomly..

not sure how to recreate the problem because it definitely was not limp mode, and car seems to drive fine now ( knock on wood)

KrnAndy

maybe, could feel like dropping the clutch slipping and dropping randomly...

no slippage in 4th and slamming on the gas

clutch pressure seems to be fine too (returns up just fine)

Dreezy562

first owner? 2nd owner? if you cant recreate it then ur good

Rusty

Bet there was something slippery spots on the road (oil or coolant most likely) and you hit it. You was accelerating, hit a spot. Rev's shoot up, jerks you backwards. Traction control kicks it. Rev's back down, jerks you forwards.

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Jhill

Any misfire counts?

KrnAndy

No. I was going at about 10mph in first gear accelerating, it happened, I let off the throttle completely and it continued to do this weird thing. Dry smooth roads, (note that I'm NOT mashing on the throttle, I wasn't spiritedly driving, just a very slow casual cruise, early morning)
This definitely was not a drivers mistake, or road conditions. The transmission DID act up but not sure why

Drove it for another day or so, but seems fine...
Noticed the clutch is a bit weird though...

The chattering of our twin plate actually chatters up the Rpms in first gear now, with clutch fully out.. Does not happen when warmed up or in other gears

I did notice though... When accelerating in first gear it's very jerky as I'm letting off the clutch and accelerating a bit now, feels like a jerky tug, like the clutch grabs and slips really quickly

Mashed the gas pedal in fourth low Rpms to see if it shoots up but no go, it seems to grab fine

KrnAndy

I wouldn't know, no cel or anything, dont know how I can recreate the problem to show a mechanic, and with no codes..

Ghostvette

My time for clutch, flywheel, csc and cmc. Given what is in this post, it appears you have a clutch that is on the edge of failing. Contact Ryan at RJM to get an upgraded CMC. GL.

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