G Power Supercharger

* g-power supercharger with 405 hp

* complete stainless steel exhaust system

* Porsche brake with 322mm brake discs

* KW-height and hardness adjustable suspension (very low)

* No Door Locks

* No rear Screen Wiper

* No antenna

* No BMW signs

* Rear spoiler in car colour

* Strut brace

* wheel spacers 5mm front, 20mm rear

* 265/40 on rear axis

* Plastic coated wheels (black)

* White indicator bulbs front and rear

* clutch stop

* 32cm diameter steering wheel with full size airbag

Coming Soon… More details and photos

BMW Z3 Wacky Gas Gauge

One of the most consistent failures in the BMW Z3 is the gas gauge. I’ve heard different excuses as to why the gas gauge fails, but rather than pretend to be an engineer or parts inspector let me just share with you some observations I have made regarding my wacky gas gauge.

Let me start by saying I never had a problem during my first year of ownership. But others were having problems during that time so I heard a lot of speculation regarding what caused the failure and I got to see what BMW’s fix was for those under warranty. I can almost pin-point the exact time mine started acting up. I was refueling and for some reason, when the gas pumped stopped I squeezed the pump trigger one more time. I don’t know why I did it, I had been warned not to yet for some reason I did it.

It was long afterwards I saw the gas gauge do its first flip-flop dance between empty and full. The error was initially intermittent, but over time it has become very consistent. Now mine always (and I do mean always) does its dance between empty and full right after I refuel. This will continue until I travel roughly 30 miles, I’ve never noticed the problem beyond the first 30 miles of a tank. Couple months ago I decided to try an experiment, instead of refilling until the pump clicks off I started buying my gas in $10 increments (never filling the tank all the way). The gas gauge never did its dance during the 4 or 5 tanks that I did the $10 thing. So at least in my case, these observations seem to back up the theory that the failure is related to the sending unit. I’ve learned to live with it, but learn from my experiences and resist the urge to squeeze that gas pump trigger again once it clicks off.

I have made the decision to live with it rather than have it fixed because I am not comfortable with the “fix”. To get to the sending unit BMW has to cut the carpet behind the passenger seat. Then they have to hook a hose and drain the gas tank (hopefully without leaving your interior smelling like gasoline). If you look behind the right hand seat you can see a seam in the carpet, this is where they will make the cut. Once the sending unit is replaced the carpet is glued back down. Sounds simple enough but I have seen more than one Z3 after this fix where the carpet flap has come unglued and ends up looking like a bad toupee. It also appears the new sending units are not necessarily any more reliable than the original ones.

I’ve owned my M roadster over four years now and my refueling habits are fairly consistent. I’ll usually refuel before the low fuel light comes on, if I push it and the low fuel light comes on then pull off at the next available gas station. I use my trip odometer to measure distance on a tankful, and on average it usually says around 240 miles since my last refueling and it will take around 12 gallons to fill the tank back up.

One day after work I pushed it a too far, the engine sputtered then quit. I zig-zagged a little and got another second or two of runtime before it quit for good. Luckily I was going downhill at the time so I managed to coast into the gas station and right up to the pump. I got lucky, and this provided me with an opportunity. I now know it takes 13.3 gallons to fill a completely empty tank. I started taking notes after that and refilling at different points on my gas gauge. It takes 8.9 gallons to fill a tank that my gauge indicates is half empty. 12.3 gallons to fill a tank right after the low fuel light comes on. I will continue to take measurements at various points on my fuel gauge and update this page.

One last final note: Remember that my fuel gauge has problems so my measurements may not be typical of most Z3s.

Glove Box Light

Here is some information on a glove box light I made. I bought a keychain flashlight that used a bright blue led for the light. I got it from LL Beans for $20, but I see them for sell everywhere. It is a sapphire crystal led, and two 3-volt lithium batteries. The cells have a 10 year shelf life. All I wanted was the led and the 2 batteries.

I took the light apart and just used the led and the area that holds the batteries, cutting the rest of the body off.

I then acquired a metal cased mercury tilt switch. Durakool (http://www.aecsensors.com) has various tilt switches. I bought part #4929 from Newark Electronics (http://www.newark.com). It was around $5.00, but there was a minimum order, or a $5 penalty. It operates at a plus or minus 7 degree angle. It is very tiny, being around 1/4 inch all round in size. I placed all the parts in a small fuse box (the one that the cylinder type buss automotive fuses come in). It seemed like a perfect candidate since the plastic part of the box slides off easily from the metal top and it is small and shallow.

I drilled a hole in the plastic part of the box for the led to come out, and the rest (batteries in their holder and tilt switch) was placed inside and held in place with electrical tape. I had previously soldered circuit board wire from the tilt switch to the light. Some final touches like an LED holder from radio shack and some chrome tape on the box gives it a more finished look.

This small fuse box was attached to the left side of the glove box and held in place with velcro. The angle of the box had to be adjusted to get the light to turn on and off at the appropriate time when opening and closing the glove box door.

Pleased with the finished results, it puts a nice blue light inside the glovebox that allows me to see the things inside.

Z3 Paint Problems

While in for a service check, I asked the BMW Center of San Antonio, Texas to look at the trunk lid to make an assessment of why the paint was fading. They stated there was nothing they could do and were not sure why it was fading. They thought it was oxidation and tried to buff it out, which did not work. Since the car was past the four year warranty, they would not repair it. Within two months, the faded area spread to almost two-thirds of the trunk lid. Areas on the left rear fender and hood have also appeared. I took the car to a third party paint shop. Their analysis was that the paint was fading between the clear coat and the base paint. If the clear coat got thin enough, it would start peeling off. The only solution is to repaint the affected areas. The fading will only get worse no matter what precautions are taken. Since I have had the vehicle, it has always received the best wax treatment and care. A decision will have to be made whether to invest money into a full vehicle paint job or put it towards a new Z3.

Editors Comments: It’s my impression that BMW Service departments will just about always avoid any kind of paint warranty repairs. I don’t think they are necessarly the guilty party as it’s BMW North America that is ultimately holding the check book. Service departments know they are going to have a hard time getting BMWNA to pay for paint repair warranties and they are just automatically on the defensive. Bottom line, its going to be an up-hill battle and you are probably wasting your time discussing it with the dealerships service advisors. Ask when the BMWNA service rep is going to be in the area and schedule an appointment to meet him. Provide him with the facts, and avoid using the word “internet”.

Stopping Brake Squeaks

For some reason I associate brake squeak with old junker cars. It was embarrassing for me when my Z3 started making those annoying high pitched squeaks every time I came to a stop sign. After some research the solution was cheap and easy.

The first thing I learned was that I misunderstood what brake squeaks were. I thought it was the friction between the brake pad and the disc that caused the squeak. Turns out that most brake squeaks are from the brake pad moving around and rubbing against the caliper.

I had heard of anti-brake squeak stuff before but I always dismissed it because I thought anything between the brake pad and the rotor was a temporary solution at best since it would wear away quickly. Once I learned this stuff was for the back of the brakes everything made since. The guy at the NAPA store laughed and said “can’t tell you how many times I’ve seen this stuff used on the wrong side”. NAPA’s CRC Brake Disc Quiet was roughly $3 a bottle, and it was more than enough for two cars.

It comes out as a thick rubbery goo, and dries in about 10 minutes. Once dry, simply reinstall the brake pad then wipe down the excess red goop that squeezes out. It’s a little messy, but you’re probably wearing rubber gloves when working with brake pads anyway.

Once installed the difference was night and day, no more brake squeaks.

Changing Brake Pads In My BMW

The very first step is verify that you have a 7mm allen wrench, it wasn’t part of my little allen wrench kit so I had to make a quick run to the local hardware store. While you are there you may want to also pick up some rubber gloves. As you know the stock brakes spread break dust everywhere. Once I had the right tool for the job replacing the pads was pretty easy.

The first (and possibly hardest) step was getting the car up on a jack and jack stand. Especially considering the BMW M roadster does not come with a jack. Once that small task was done and the wheel was removed the rest was fairly easy.

If you are working with the right rear wheel or the left front wheel there will be a brake sensor (blue arrow). This sensor is clipped into a notched out area of the brake pad. Get your fingers as close to the brake sensor as possible and wiggle-pull it free.

The next step is to remove the retaining spring. I used a few choice curse words to aid in its removal, you will want to squeeze and push in on the clip (red arrows) while lifting and pulling out on the back (yellow arrows).

On the back side of the brake, there are two plastic caps that cover the 7mm hex bit guide screws. The plastic caps can be pulled off with your hands, they are snapped into a rubber housing. Once the caps are out of your way use the 7mm allen wrench to remove the guide screws. The screws should be completely removed.

The only thing holding the brakes in place now is brakes themselves. If you are having trouble working the caliper free apply constant even pressure on the brake piston by pull on the outside of the brake (use caution – remember your car is up on a jack and jack stand). You are not going to be able to compress the piston with a single yank, just use medium sustained pressure and you will feel the piston loose pressure and release. It took me about 40 seconds of medium pressure for this to happen.

Once the caliper is removed, replace the inner and outer brake pad. The inner brake pad is clipped into the brake piston, pull straight out to remove.

The outer brake pad was just kind of stuck there. Note the sticky stuff on the stock outer brake pad, if the new pads you are installing do not have this you will probably want to take a look at my Stopping Brake Squeaks article.

Once you have the new pads in place, you may have to put some more pressure on the piston in order to reinstall the brake caliper since the new brake pads should be thicker than the worn ones you just removed. The rest of the installation is just retracing the steps you took to remove the caliper.

TWO VERY IMPORTANT NOTES: You will need to pump your brake pedal several times to get pressure back to the brakes. Use extra caution the first time you drive after replacing the pads.

When new, brake pads have a slightly rounded surface that ensures once broken in you get a maximum contact patch. But until they get fully broken in you are concentrating the friction to a smaller patch. This means that when brand new the friction/heat is in a smaller area so you should avoid overheating the rotors.

Under The Hood

Before – One of the pleasures of owning an M roadser is to show off your engine.

After – I decided to add a little more spice in the look of it. I started to add some chrome accent. Most of the parts came from Ron J. Stygar expect for the strut bar, which came from Paul Ebeyer Sr.

After – Here’s what I’ve added;

* Battery Ground post

* Diagnostic connector cap

* Engine Lift point

* Oil filter lid

* Oil filter cap

* Radiator Cap

* Steering pump cap

* Radiator Spacer screws

* Valve cover nuts and washers

* Various Z8 nuts

* Windshield wiper jug screw

After doing so I felt that I could go the extra mile and have my valve cover and fuel line cover painted in Imola Red. Needless to say that I was really impress with the result.

I bought a new set of cover since I have use a lot of Armorall of these cover. My dealer told me that even if he would prep the cover very well, I could end up with fish eye on the cover.

After – Here’s the part number for the covers

* 11-12-1-404-466 – BMW M Power valve cover

* 13-54-1-740-160 – Fuel line cover

This really didn’t bring any power to the car but it sure looks more beautiful.