Boost Leak tester - 1.8TQ

[Mr K]

I think I may have a minor boost leak and want to do boost leak test as part of my maintainance.

From what I've read you can do damage if you do it wrong, so whats the correct procedue and what sort of pressure should I aim for during the test?

I assume I need to make a blank for the turbo intake with a tyre valve in it to pump it up - what size is the turbo intake so I can order a bit of hose.

I assume you cant do it from the MAF end of the TIP. Access would be a lot better but I guess the DV etc will play havok with that.

 

[Bradderz_1988]

I use this method, take off the oil cap, remove the hockey puck on the TIP and block off the TIP, now for the tester i used this homemade cap that pops directly on the MAF (as i run open filter i can just remove the filter off the MAF) with a tyre valve pulled through and just inflate with tyre inflater connected up to an air line, you might be best off with a pressure regulator of some sort to hold pressure while you check for leaks, and i also remove my boost gauge and tap it to where my FPR pipe is to monitor pressure, as for pressure i normally stick around 15psi (just over stock) but id off thought if your running mega boost just go a little over your peak boost reading.

Homemade tool exhaust extractor cap with tyre valve.

id swap out your vac lines and DV if not already done that as no doubt they'll be goosed !!

 

[Mr K]

Thanks, that’s really useful. A few more questions!

Is the stock MAF 2.75”?

I’m running stock boost at the moment, and have a big compressor in the garage so pressurising it is not a problem. I don’t know how low the regulator goes – but I will be able to pump it upto 12-15ish PSI pretty easily. I guess it slowly leaks out through the piston rings anyway.
I had seen this kit and was going copy it:
B5 96-01 1.8T K03K04 by turboboostleaktesters.com

I assume the "1” brass blank” they refer too is for where the hockey puck is disconnected?

I was going to fit a 710N, and redo a load of the vac hoses. Maybe a silly question but what is the best vac hose to go for?

 

[Bradderz_1988]

Thanks, that’s really useful. A few more questions!

Is the stock MAF 2.75”?

I’m running stock boost at the moment, and have a big compressor in the garage so pressurising it is not a problem. I don’t know how low the regulator goes – but I will be able to pump it upto 12-15ish PSI pretty easily. I guess it slowly leaks out through the piston rings anyway.
I had seen this kit and was going copy it:
B5 96-01 1.8T K03K04 by turboboostleaktesters.com

I assume the "1” brass blank” they refer too is for where the hockey puck is disconnected?

I was going to fit a 710N, and redo a load of the vac hoses. Maybe a silly question but what is the best vac hose to go for?

yeah stock maf is 2.75", yeah it will slowly drop off as it passes the rings, 1" blank is for the hockey puck, i used 3mm ID vac pipe off ebay about 1 metre should do it 2 if you have a Boost gauge but you normally get piping with most boost gauges.