1.8t - Car randomly stutters under light load

[Sirocco20348]

Hey guys, just hoping someone can point me in the right direction.

My car has started randomly stuttering/jerking under light accelerating conditions. For example while on cruise control on flat road or when driving normally.

With full boost, it doesn't stutter, but the car doesn't sound 100%, maybe like air venting into the atmosphere?

I only noticed the problem this morning while on my way to work.

Thanks

[JustCruisn]

Could be heaps of things.
I'd check for air leaks. I had a massive hole in the elbow of a line near behind throlle body, right side near the coolant sensor. I could hear the sucking air over the idling engine. It causes a strange fluctuation and sometimes hesitant acceleration.

Or the ignition control module could be dying which will drop a cylinder, that will make it run like **** and sound rough like a Subaru.

[aprr32]

Or the small vac hose that goes to the fuel press reg.

[Sirocco20348]

Thanks Guys,

I created a boost leak tester and the results are in.... my car has at least 2 leaks... I cant hold pressure at all...

1) A leak from a small pipe connecting from under the intake manifold (06A103221C)
2) Another leak somewhere near the intercooler, maybe one of the major pipes.. about to remove the front bumper and wheel etc to have a look..

I can only imagine how much power I am losing from these leaks.

Anyone who hasn't boost leak tested their car, I would strongly encourage it.

Not sure if this will fix my problem but its a good start. Ill post pictures of my Bunnings boost leak tester this afternoon. Cost $20.

[Sirocco20348]

Farout my intercooler has a hole in one of the vents... Does anyone have any recommendations on how to fix this? Or is it best to source a 2nd hand one. I don't want to buy a front mount just yet. Id rather stay with my side mount for financial reasons atm.



Also this connector was hanging down the side of the intercooler... its not a vacuum hose.. anyone know where it is meant to go?

[Sirocco20348]

For anyone that is curious about the boost leak tester... This is hooked up to my bike pump, but you could also get an attachment to hook up to a spare tyre, or even change the nozzle to fit onto a compressor...

[h100vw]

Clean with brake cleaner and araldite it up.

[Sirocco20348]

Thanks Gav

I will get some Permatex Cold Weld from super cheap and some brake cleaner.

Permatex Cold Weld Bonding Compound - 57G - Supercheap Auto Australia

Any ideas on that random connector?

Also if anyone else is interested in this link, I found a $50 silicone hose kit on AliExpress... it has Samco printed on it... Surely its upto the task.

http://www.aliexpress.com/item/VW-GO...684240293.html

[h100vw]

I'd google the part number on the sensor. It doesn't look like the outside temo sensor, but it might be?

[JustCruisn]

That random connector is just a random connector.
It should be positioned behind the driver side head light. There is a clip for it.
It does exactly nothing. If you pull off the end piece you will find it is nothing but a piece of plastic just to keep water out of the electrical connector. There is voltage in it however.
I think it might be for the MAP sensor on the intercooler, which we don't have.