Shudder at acceleration
Thread Starter
Newbie
Joined: Jul 2020
Posts: 7
Likes: 1
From: Toronto
2012 GLK 350 4matic
Shudder at acceleration
Hi. First time poster. Hoping I can get some advice.
Lately when I drive in the morning I noticed a brief shudder when I accelerate through 20km/40Km/60k/80Km per hr. It sounds like going over a rumble strip. There’s also occasionally a slight flicker in rpm. Sometimes more pronounced than others (especially pronounced on smooth pavement) After driving for 20-30 mins (especially on the highway) I can’t reproduce the same shudder at all
the Tranny was just services in the last 3 months and new tireand wheel were just balanced.
I know a torque converter can cause this, but can the TC shudder go away after the tranny fluid heats up?
just passed 200,000km but has been serviced to specs or better and mainly highway drive at constant speed.
brought it to my shop and they scanned the car and checked the fluid levels. Fluid was good and no faults in the drive train. Turns out the primary flap in the intake manifold wasn’t engaging. After some driving the secondary flap engages (and the shudder stops) being fixed now
Lately when I drive in the morning I noticed a brief shudder when I accelerate through 20km/40Km/60k/80Km per hr. It sounds like going over a rumble strip. There’s also occasionally a slight flicker in rpm. Sometimes more pronounced than others (especially pronounced on smooth pavement) After driving for 20-30 mins (especially on the highway) I can’t reproduce the same shudder at all
the Tranny was just services in the last 3 months and new tireand wheel were just balanced.
I know a torque converter can cause this, but can the TC shudder go away after the tranny fluid heats up?
just passed 200,000km but has been serviced to specs or better and mainly highway drive at constant speed.
brought it to my shop and they scanned the car and checked the fluid levels. Fluid was good and no faults in the drive train. Turns out the primary flap in the intake manifold wasn’t engaging. After some driving the secondary flap engages (and the shudder stops) being fixed now
Last edited by BalaJake; Jul 29, 2020 at 09:45 AM. Reason: Resolved
MBWorld Fanatic!
Joined: Sep 2015
Posts: 2,585
Likes: 343
2013 glk 350
I have a 2013 with 62000 miles , I recently had a shudder on hard acceleration and downshifting . I never had fluid done so I got it changed . The mechanic stated low fluid was a possibility . It seems ok now.
Who did your trans service ? Was torque converter drained ? Did they warm the motor to only 45c while setting the level ?
Are you leaking any fluid? Is it possible your low on fluid ? Maybe the valve body is causing it? That can be serviced easily.
I would want to know exactly how much fluid is in the trans. That means carefully draining it and refilling . And probably service the valve body.
I’m just learning about this as I’m experiencing problems also. I’m not a pro. I
really don’t know if the valve body could cause shuddering . But it’s probably the cheapest thing that can be fixed fairly cheaply.
Who did your trans service ? Was torque converter drained ? Did they warm the motor to only 45c while setting the level ?
Are you leaking any fluid? Is it possible your low on fluid ? Maybe the valve body is causing it? That can be serviced easily.
I would want to know exactly how much fluid is in the trans. That means carefully draining it and refilling . And probably service the valve body.
I’m just learning about this as I’m experiencing problems also. I’m not a pro. I
really don’t know if the valve body could cause shuddering . But it’s probably the cheapest thing that can be fixed fairly cheaply.
Thread Starter
Newbie
Joined: Jul 2020
Posts: 7
Likes: 1
From: Toronto
2012 GLK 350 4matic
Thanks. I drove it about 25 mins to my mechanic yesterday. After driving it and heating whatever is the issue is seems to go away.
so I left overnight and they’ll check again this morning.
I’ll posting the findings since you’re experiencing something similar.
cheers,
jacob
so I left overnight and they’ll check again this morning.
I’ll posting the findings since you’re experiencing something similar.
cheers,
jacob
MBWorld Fanatic!
Joined: Sep 2015
Posts: 2,585
Likes: 343
2013 glk 350
You need to ask him the procedure he used to check level, it entails running the motor with a scan tool on it until it only reaches 45c (I believe ) then putting in the plug. Did he do the torque converter ? Then you have to run it through the gears. There are good videos of it. You should look one up on you tube, or I can send you one. Maybe the mechanic screwed up .
Thread Starter
Newbie
Joined: Jul 2020
Posts: 7
Likes: 1
From: Toronto
2012 GLK 350 4matic
Thanks For the tip. They did run through all those steps. Turns out the primary flap in the intake manifold wasn’t engaging. After some driving the secondary flap engages (and the shudder stops) it’s being fixed now
