2006 Not Starting and Leaking Brake Master Cylinder

I have a 2006 Jetta 5 Speed, 180,000 miles. I am new to TDI's but do have a degree in Diesel mechanics and plenty of experience working on farm equipment.

A couple weeks ago, after night class, I got in my car and went to start it and it wouldn't turn over. All gauges, radio, lights all work just fine. I pumped the clutch and turned it on and off a few times, finally it started like normal. Once I got home, I turned it off and started it a few times, no issues. The next morning it wouldn't start again, kick the clutch a few times it turned over like normal. Fast forward a week, progressively taking more and more tries to start. The last day I drove it, it started acting up a little more. Once I got the starter to go, it would just click a few times, like a dead battery or bad solenoid and then it would turn over like normal. Later that day it did start clicking more and made all the lights and gauges flash while trying to start. Battery is newer and all the gauges, lights, radio, etc.. working just fine. I pulled it in my shop and parked it. I haven't had time to think about it. I am thinking there is a loose connection somewhere, I am going to search tonight. I do have a new starter on hand just in case. I was thinking clutch switch, but my experience with those is when they fail, they fail. No partial power or starting. What are your guys' thoughts on this? ***FIXED

Also, my brake master cylinder is leaking. I am going to replace that this weekend. I am guessing it should be a pretty straight forward deal, unless there is something unique about TDI's that I need to know. Is there anything special I need to know? Does anyone have suggestions for a parts brand for the master cylinder? Debating on just getting one from the local parts store with the lifetime warranty.


Thanks in advance.

On the master cylinder, pull the pedal assembly and do it all on the table. Trust me.

Remove the plug from the engine bay on the master cylinder, take the hydraulic line out, then up under the dash remove the 3 nuts holding the assembly on and take it all out. Build it all up on a bench and then put it back. Its next to impossible to do it laying in the floorboard.

Also, if i'm not mistaken the master slave stuff has been updated and you need to replace everything in order to get the stuff to seal correctly. I'm not 100% on that, I just replaced it all and didnt ask any questions.

I think he mentioned BRAKE master cylinder.

No need to pull any pedals to do that. You will need to remove the battery to get access to it. It is held by two nuts (tightening torque is 50 Nm). You will need to undo the plumbing and wait for the fluid to leak out. Use a catch can, you don't want to spill the brake fluid anywhere on the paintwork.

The master cylinder will have an o-ring. It can be safely reused (if it doesn't come with the new MC) but if you want piece of mind feel free to renew it. Will be a bit costy at VW dealership for a simple o ring.

I'm grabbing some popcorn and sitting back to watch this. Wonder what pedal and brakes feel you will have after master cylinder replacement.

Well, I fixed the starter issue. I changed my transmission fluid a few weeks ago. I filled it through the hole for the reverse sensor which is fairly close to the starter. I guess I bumped the trigger wire and it worked its way loose. That was an easy fix.

Still haven't messed with the brake master cylinder. Thank you henrick for the advise.

I did find a new problem. I had the car up on ramps overnight. When I walked in tonight there was a puddle of my new transmission fluid on the ground. A big puddle. Looks like the seal for my axle shaft is leaking. So if anyone has any helpful pointers, throw them my way.

upchurch17 said:

Well, I fixed the starter issue. I changed my transmission fluid a few weeks ago. I filled it through the hole for the reverse sensor which is fairly close to the starter. I guess I bumped the trigger wire and it worked its way loose. That was an easy fix.

Still haven't messed with the brake master cylinder. Thank you henrick for the advise.

I did find a new problem. I had the car up on ramps overnight. When I walked in tonight there was a puddle of my new transmission fluid on the ground. A big puddle. Looks like the seal for my axle shaft is leaking. So if anyone has any helpful pointers, throw them my way.

Click to expand...

You may be lucky...

When you take the old DSG filter off there is a odd pocket that collects alot of old oil that falls out of the filter when you remove it. Its directly beside the filter. You have to usually soak up this oil with several rags. If you didn't, my guess would be that when you had the car on ramps this oil ran down the back of the tranny right where the drive shafts connect.