Posted by Chris More | Posted in audi | Posted on Sunday, March 07, 2010
During my quest to figure out the boost problem in the RS6, I have had multiple people tell me that there could be a leak somewhere in the system. If you have had a turbo car, you know that a leak could be almost anywhere. It could be as simple as a leak in a turbo hose to a cracked intercooler. I searched online and found plenty of homemade boost leak testers but nothing for the Audi RS6. With the combination of the rarity of the RS6 and knowing that most owners don't do their own work, there was a lack of documentation online to do many tasks.
I decided to take on the task of figuring out how to test for boost leaks and it really wasn't too difficult. I went to Lowes and spent about 30 minutes trying different combinations of fittings and tubes until I finally found something that would work.
Below is what I picked up and they include a 3" PVC cap, 4" x 3" rubber downspout converter, 4" test plug, pressure regulator, air fittings, and some host clamps. I bought J-B weld however I did not need it.
First, you need to cut the lip off of the rubber downspout converter as you only need the outside piece to use as a coupler.
Take a 3/8" drill bit and drill a hole into the end of the plastic cap. Then use a reamer to open the hole up to something just smaller than the threads in the air regulator. Start out slowly so you do not take off too much plastic. You want to be able to screw the regulator into the cap with enough force that it creates a tight seal.
You will need to put teflon tape on the threads of the air pressure regulator and screw it into the plastic cap. If you aren't sure it is sealed tight, you should use some epoxy or J-B weld on the threads. Screw another air fitting on the other side of the regulator. You will probably not need any teflon tape on the non-cap side of the regulator but your application may vary. Finally, take the rubber coupler created earlier and clamp it on to the end of the cap. Make sure you leave enough of the coupler off of the end of the cap to allow for clamping to the air intake.
Now it is time to mount the leak tester on the intake system but you will first need to remove the silver air intake runners. To remove the runners, loosen the hose clamps and remove the 2 screws (per side) on the black plastic piece above the bumper. Once the runners are removed, pull out the leaf guards and sit them aside.
Take the 4" test plug and tighten it up on the passenger side intake.
Remove the screws on top of the intake system to expose the air filters. Remove the air filters and inside the side intakes is a small hole at the bottom. Use a piece of duct or aluminum tape to cover up the hole but make sure you remove it when you are all done! If you don't cover up this hole you will not build any pressure.
Finally, you are ready to hook up the tester and find your leak! Connect the air pressure regulator, turn the adjustment knob all the way off (clockwise), and turn on your air compressor. You don't need much more than 30psi on the air compressor as you will adjust the final pressure with the boost leak tester regulator.
When I performed this test, I found out that a substantial amount of air was leaking around the MAF sensors. The next step for me to is replace the gaskets on top and bottom of the MAF sensors and test again!
Please let me know if this was helpful or if you have any questions.
I decided to take on the task of figuring out how to test for boost leaks and it really wasn't too difficult. I went to Lowes and spent about 30 minutes trying different combinations of fittings and tubes until I finally found something that would work.
Below is what I picked up and they include a 3" PVC cap, 4" x 3" rubber downspout converter, 4" test plug, pressure regulator, air fittings, and some host clamps. I bought J-B weld however I did not need it.
First, you need to cut the lip off of the rubber downspout converter as you only need the outside piece to use as a coupler.
Take a 3/8" drill bit and drill a hole into the end of the plastic cap. Then use a reamer to open the hole up to something just smaller than the threads in the air regulator. Start out slowly so you do not take off too much plastic. You want to be able to screw the regulator into the cap with enough force that it creates a tight seal.
You will need to put teflon tape on the threads of the air pressure regulator and screw it into the plastic cap. If you aren't sure it is sealed tight, you should use some epoxy or J-B weld on the threads. Screw another air fitting on the other side of the regulator. You will probably not need any teflon tape on the non-cap side of the regulator but your application may vary. Finally, take the rubber coupler created earlier and clamp it on to the end of the cap. Make sure you leave enough of the coupler off of the end of the cap to allow for clamping to the air intake.
Now it is time to mount the leak tester on the intake system but you will first need to remove the silver air intake runners. To remove the runners, loosen the hose clamps and remove the 2 screws (per side) on the black plastic piece above the bumper. Once the runners are removed, pull out the leaf guards and sit them aside.
Take the 4" test plug and tighten it up on the passenger side intake.
Remove the screws on top of the intake system to expose the air filters. Remove the air filters and inside the side intakes is a small hole at the bottom. Use a piece of duct or aluminum tape to cover up the hole but make sure you remove it when you are all done! If you don't cover up this hole you will not build any pressure.
Finally, you are ready to hook up the tester and find your leak! Connect the air pressure regulator, turn the adjustment knob all the way off (clockwise), and turn on your air compressor. You don't need much more than 30psi on the air compressor as you will adjust the final pressure with the boost leak tester regulator.
When I performed this test, I found out that a substantial amount of air was leaking around the MAF sensors. The next step for me to is replace the gaskets on top and bottom of the MAF sensors and test again!
Please let me know if this was helpful or if you have any questions.
