Engine Shudder

[TimmyCee]

2015 Jetta SEL 6 speed manual- 72,800 miles, is having an intermittent engine shudder in all gears, with no codes. I first noticed it in 5th gear while gently accelerating around 55 MPH. It then began occurring randomly in all other gears/speeds as well, most noticeably when pressing the accelerator; I sometimes feel a quick RPM drop off while sitting in neutral too, but its gentle as I'm obviously not moving. The best way to describe what it feels like would be if you pressed the clutch for a split second and felt the car buck. RPM seems to drop when this occurs. Note: This is not occurring while shifting, but rather while the car is already in gear. I had to leave the car with the dealer and have the technician drive it a few days as you never know when it will occur. It seems the most likely conditions for it to occur are on the second drive of the day, after the car sits for an hour or more. Technician is thinking pressure plate or flywheel, but I am not convinced the symptoms match. VW of America is suggesting a transmission teardown, which my extended warranty would not cover unless an internal part is to blame. I am not mechanically savvy, so please respond accordingly

 

[ApproachMedium]

If you have not replaced the pigtail on your number 1 injector, it will probably go bad soon. That could be it, it most def is probably your EGR clogged up. I have a DSG car and mine does exacrly this, and it was the EGR. Cleaning it helped a ton, but ultimatly i had to replace my cracked DPF to get it to behave 100%. Seeing you have a 2015, the DPF cracking i think is less likely, but theres somebody here that can answer that.

I highly doubt it is your trans. tell them to start looking at your EGR system.

 

[bmwM5power]

does it happen when you take off releasing the clutch?

 

[oilhammer]

CKP sensor is flaking out. Unless they put a scope on it (which is next to impossible), they'll never see the signal dropping out.

 

[ApproachMedium]

What makes it next to impossible to put a scope on the sensor? just the location its in? No other place to probe it at?

 

[oilhammer]

Tricky location, tiny fragile wires. It would be faster and easier to just put a new sensor in and give it a shot.

 

[ApproachMedium]

For the 71 dollars, ill def take your word for it and just replace if it ever happens!

 

[oilhammer]

Here is a thread about this issue:

Random Engine Hesitation

Hey Mike or anyone. So I took out the airbox, and I can't seem to find this bugger, is it below the starter?... actually I'm assuming it can be reach from the top, because that is the way on a BRM You go at it from underneath. This video is the best I’ve found that shows where it is...

forums.tdiclub.com

 

[TimmyCee]

does it happen when you take off releasing the clutch?

No, it’s not occurring while shifting.

 

[TimmyCee]

CKP sensor is flaking out. Unless they put a scope on it (which is next to impossible), they'll never see the signal dropping out.

The camshaft position sensor was replaced, and I am still having the same symptoms.

 

[oilhammer]

Well, you will... because the CMP sensor is not the CKP sensor, which is what I recommended get replaced. Derp.

 

[TimmyCee]

Well, you will... because the CMP sensor is not the CKP sensor, which is what I recommended get replaced. Derp.

As I said, I’m not mechanically savvy, but thanks for your response nonetheless.

 

[TimmyCee]

I intended to provide an update earlier, but I wanted to ensure the "fix" really worked. Well, with about 2400 miles under my belt, I can say that oilhammer was on the money and the Crank shaft Position Sensor being replaced has fixed my issue! I'm still disappointed in VW of America, in that this was not something they considered, but I am happy to be driving a healthy TDI once again! Thanks everyone!

 

[pedroYUL]

...you mean CRANK position sensor, but most of us are following the conversation