Still need help? Below we have addressed the most frequently asked questions regarding a boost gauge installation in a mk4 1.8t. This includes what to buy and how to install it.

Do you sell a complete kit?

Yes, we sell many complete kits based on our mounting solutions. If you would like a complete kit, check out our Gauge Solutions. Remember, our setups are only complete if purchased as a solution.

If you want to do something different than the complete packages we sell, see below.

I want to install a boost gauge, but I want to use a different pod. What do I need?

No problem, many people install boost gauges in other locations. Our website and our product line is setup so that you can purchase everything down to the the last nut and bolt. As soon as we package something, a customer comes along who needs individual components. Every installation will be different based on what mounting pod you are using, what lighting you want, etc, etc. The following information should clear everything up:

First, what pod are you using? The main reason to ask this question is space. Our a-pillar pod and triple gauge panel have been designed around our tubing kit which includes a rather large push-in fitting to easily connect the tubing. Many other gauge pods on the market are not large enough for this fitting and have not been designed to use such a fitting.

If you are using an a-pillar pod not made by 42, we recommend you purchase a 90° Boost Gauge Fitting to compliment our tubing kit. Many a-pillar pods on the market are designed as small as possible and leave no room for tubing fittings.

If you are using a pod that mounts on your steering column, you will also need the 90° Boost Gauge Fitting. These pods are designed to use 90° fittings no matter what.

Do I need a tubing kit?

YES! If you purchase an individual VDO or SW gauge from 42, you need to buy a tubing kit as well. Stupid, right? Well, not everyone needs the 1.8t based tubing kit. Many TDI owners prefer the TDI tubing kit, and some people choose to build their own tubing kits.

Don't forget the 90° Boost Gauge Fitting if you are using a pod with a tight fit. See above for more info on this fitting.

Do I need to buy a T fitting?

No, not if you are purchasing the tubing kit. Our tubing kit includes everything you need to plumb a boost gauge in a 1.8t VW. It includes the push-in fitting to connect tubing to the gauge, tubing, and a restrictor T fitting.

The restrictor T fitting which we include prevents gauge "buzzing" in all 1.8t applications. The fitting has been molded in one piece to include a restriction in the center barb. The fitting will only work if installed correctly. The center barb must be connected to the boost gauge tubing. Only the center barb is restricted.

Do I tap the FPR or DV?

Which line to tap is widely debated. What's the answer? Any line which will give you a clean signal from the intake manifold is the correct line. Let's simplify it a bit - the two most popular locations to get a boost and vacuum signal is the FPR hose and the DV signal line.

The FPR (Fuel Pressure Regulator) line is used because it is a direct line from the intake manifold and the hose is small. The DV (Diverter Valve) line is often used because it is easy to access and also offers a vacuum and boost signal. We recommend tapping the FPR line.

Why? The FPR line connects directly to the intake manifold. Tapping this line for the boost gauge offers a crisp reading and the hose is the same size as the hose we provide in our tubing kit. Tapping the DV works, but there is a host of valves and other connections between the manifold and the DV. Mainly - the N249 valve controls the DV's action. If the N249 valve controls the DV, it will also be controlling your boost gauge. Some people say that tapping the FPR valve is unsafe, arguing that a leak at your boost gauge connection will alter fuel delivery. It will, however you'll see this leak immediately at your boost gauge! The T fitting we provide purposely fits tight in the FPR line and the boost tubing. If installed properly, no leaks will occur and there is nothing to worry about. (FYI, our T fitting is too small to use on the DV line. If tapping the DV line, you will need to create your own T fitting.

Do I need to use clamps on my T fitting?

Our T fitting fits very tight on purpose. We don't believe clamps are necessary, but if you would like to use a clamp, we recommend using a small zip tie.

On to electrical...

When is a wiring kit included? Does your wiring kit include everything I need?

Wiring kits are always included with the purchase of a gauge. Our boost gauge wiring kit includes the proper wiring and connectors to install your gauge. We include typical crimp style connectors. If you are unfamiliar with crimp connectors, ask a friend! You will need a set of crimping pliers to successfully crimp the connectors. Check your local hardware store for a set of crimpers. Don't be afraid to buy a tool to complete the job. We promise you'll use them again!

The only area where we do not include a connector is where you will tap the dimmer switch. We recommend soldering this connection always. If you are unable to solder and would like to use a wire tap, be sure to strip each wire to ensure a good connection.

How do I tap my dimmer switch?

This is covered in the VW Tips and Tricks section of our Boost Gauge Instruction Manual. Also, be sure to check out the ground wire section.

Are LEDs included with each gauge?

No! We have so many versions of LEDs that it makes no sense to include the LED. Each gauge comes with a white 194 light bulb which we typically leave in place when shipping a gauge. If you would like to light the gauge up in a color, you'll need an LED. You have many options for LED lighting including our 194 wedge style LEDs and our Perfect Match LEDs.

What LED provides the best match to my 1.8t cluster?

Options, Options!

VDO Gauges
If you are using a VDO gauge, our Perfect Match LED is a perfect match to the cluster. We achieve this match by using 9 LEDs of the exact wavelength used in the stock cluster. This solution is more expensive than a regular LED, but the match is spot on.

You may also use one of our blue 194 wedge style LEDs. While not a perfect match, one of these LEDs will give you a blue lit gauge at little cost.

Another option commonly used is a red 194 LED. Our red 194 wedge style LED matches the surrounding red lit dash components perfectly. A red lit gauge blends in well and is often considered more stealth.

Stewart Warner Gauges
If you are using a Stewart Warner Boost gauge, our Perfect Match LED is not compatible. We have yet to develop a bulb for the SW boost gauge. The bulb socket in the SW gauge is significantly smaller than the VDO and requires us to create a new base. Development is under way, but no ETA is promised yet.

If you'd like your gauge to illuminate blue, grab a blue 194 wedge style LED. While not a perfect match to the cluster, the gauge still looks great! Stewart Warner gauges have been designed to illuminate well at night, and therefore respond great to the use of LEDs.

Another option commonly used is a red 194 LED. Our red 194 wedge style LED matches the surrounding red lit dash components perfectly. A red lit gauge blends in well and is often considered more stealth.

Other boost gauges & our products - what fits what?

It's no secret that VW owners are constantly looking for a different combination in the boost gauge world. Often times, our mounting pods, tubing kits, and LEDs are used with these gauges. So what fits and what doesn't?

Any 2 1/16" or 52mm boost gauge will fit our a-pillar pod and triple gauge panel.

Our tubing kit is designed to fit any boost gauge that has a male 1/8" NPT connection on the back. Our tubing and T fitting functions as normal no matter what gauge is used. Don't forget space issues! (covered above in the second question)

Our Perfect Match LEDs have been designed to fit the VDO gauge. They may fit other gauges with modification to the gauge or LED, however we cannot recommend or warranty the PM LED system when used in a gauge other than VDO. The dimensions of the PM bulb is listed on the PM LED page for your reference. You may find this information helpful in making the PM LED bulb fit. Use some judgment - modified bulbs cannot be returned.

Our 194 LEDs will fit any gauge that uses a 168/194 wedge style light bulb. Find out what will fit your gauge before buying! Keep in mind, LEDs work best when used in a backlit gauge. They do not work well in gauges which are primarily side lit. Side lighting is old school and relies on the volume of light provided by a light bulb.

Still confused?

Check out some of the How-Tos available on the forums of VWVortex. A plethora of information is available in the 1.8t engine forum. Use the FAQ at the top of the 1.8t engine forum or do a search to find some helpful how-to guides

We hope this FAQ has addressed some of the simple questions relating to your boost gauge install. If you still need help, feel free to send us an email at sales@42draftdesigns.com. Please keep in mind, we only provide assistance for our products! We cannot give you mounting advice for your steering column gauge pod, or diagnose wiring problems with other types of gauges.

If you are still totally confused, don't hesitate to contact a local shop for assistance. There's nothing wrong with admitting you're in over your head. Have a local shop install the gauge for you, and most importantly ask them to let you watch & teach as they work.

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