BMW E36 Blog

I wrote seven articles until now about how you can make your BMW lights turn on automatically at night. I will summarize these posts for you in case you have missed them. In the first post, I proved that this should be something easy to implement inside a BMW E36 car. In the second post, I presented a circuit diagram that will help you create the electronic circuit that is supposed to control your lights and turn them on automatically when it gets dark. Of course, if you don’t know how to implement such a circuit or you simply feeling too lazy to do it, you can ask some electrician to do it for you. I’m sure he will agree if you paid him $20. In the third post, I wrote about my first attempt to implement this circuit and told you that it’s partially working but it needed some enhancements. In the fourth post, I created a video with the circuit implemented on breadboard and connected directly to my brother’s car lights. In the fifth post, I soldered the circuit on permanent board and showed you exactly how I intend to use it inside my car. In the sixth post, I posted 4 videos that I shoot while testing the auto light system. In case you didn’t see these videos I suggest you check them first before proceeding. In the seventh post, I talked about a problem in controlling the headlights of the car (low beam lights). Until that time, I was able to get my dashboard lights and the angel eyes lights to turn on automatically at night, but not the low beam lights.

When I connect the circuit to control the low beam lights, I hear a buzzing sound that comes from the relay which is supposed to work as an electronic light switch. Normally the buzzing sound indicates that the relay is connecting/disconnecting really fast and that what causes the buzzing sound. So, I tried to analyze the problem to find out what is really happening.

It’s all explained in the electronic diagram below:-

I think that when the Autolight circuit sends a signal to the relay, the relay simply closes the switch which turns the headlights on. The problem occurs when the switch is closed which makes both the relay and the headlights to become connected in parallel and since the headlights resistance is much lower than the relay resistance, the relay simply disconnects which makes the headlights turn off. When the headlights turn off, the electric current passes again through the relay which makes it connect again and thus turn the headlights on again. Of course, this happens very fast which results in a buzzing sound from the relay because it’s connecting/disconnecting very fast. I think I will need to make some change to the circuit to isolate its power source somehow from the headlight power. But how can I do this? this is the big question 😀 . If you have any ideas, please feel free to share them.

BMW E36 Blog: The ultimate BMW E36 M3 information source.

Hi Guys,

I presented some Great BMW E36 Internal Lights photos in a post couple days ago. One of the things that I didn’t even know they existed in BMW E36 cars is the Harmon Kardon audio system. The cars with this optional audio system has a switch that is labeled "HIFI". In that post, I asked you about this switch and if anyone has it, so I got a reply from Seth and he was so kind to provide extra information about this option. You can read the description in his words below:

First off, it has 10 speakers (supposedly) although I have only seen 8 discussed in the forum I belong to. Maybe I was wrong about the subwoofer, because no one had mentioned it. It sure sounds like there’s one, though! (Tony: Valery, can you help?) The only major difference I remember from my first M3 without the upgrade, is the speakers in the front kick panels (granted it’s been 2 and a half years since that car, but I don’t remember any speakers down there), the HIFI switch that turns on an amplifier located in the left side of the trunk, next to the shock tower, and the different speakers with Harmon Kardon (HK) on the speaker shield.

The biggest problem with them is that the mid-range speakers in the front doors are prone to self-destruction at relatively low volume levels. The largest contributing factor is the automatic volume adjustment as the car gains speed (Tony: Wow! that’s a cool feature, isn’t it?). I blew my own that way! Adjust the volume level in the driveway, make it onto the freeway, and KA-POP!

BTW, if you have that annoying feature, I just learned how to fix it while I was researching the Harmon Kardon (HK) stereo. First, you start with the stereo off. Turn it on, and hold the "m" button for approx. 10 sec. The serial # of the radio should appear on the screen. Once it does, use the + and – buttons until you see GAL 1-6 . Then use the < and > buttons to adjust it up or down. 1 is the lowest change, and 6 vice versa. I believe that should also work on British BMW’s as well, even though it was explained for an American M3.

These are some photos of the Harmon Kardon audio system:

Hi all, I found a post on the bimmer forum made by MParallel from the Netherlands. In that post, he took some great photos of the interior of his car at night. I have to say, these photos made me speechless. They’re just great!. Take a look at the CD player, the Phone and the illuminated M3 shift knob. Also take a look at the HIFI switch. This is the first time I see that switch. It seem when you turn it on, it separates the frequencies better and sends a more clear signal to the speakers. Overall, this is one of the best illuminated interiors that I’ve ever seen. What do you guys think? Do you have the HIFI switch?

Take a look:-

I’m having 3 problems with the electric fan in my car.

First, I know that the electric fan should have 2 speeds: Low and High. My electric fan does work on the high speed only, I guess that I’m having a problem here. I also noticed yesterday that the temperature gauge moved a little bit towards the one clock instead of the normal 12 clock position when I left the engine running (with the A/C on) and went to grab something. The second problem that I have with the fan is that whenever the fan kicks in, the RPM bounces for like 20 seconds or a little bit more, then it returns to normal.

The third problem happens usually after I reach home and turn my engine off, the electric fan kicks in and keeps working for like 30 or maybe 40 seconds before it stops.

I noticed these problems before (except for the temp. gauge one) but I didn’t pay much attention to it until yesterday when I popped up the hood and decided to trace how the electric fan is supposed to work. The task is simple; there’s a coolant sensor that is placed in the returning hose to the car’s radiator. This sensor is supposed to keep watching the temperature of the coolant and to send a signal whenever the coolant temperature exceeds a certain value (176F, 80 C according to Bentley Manual).

To my surprise, I found that the electric fan power source is not connected to any special part that is connected to the ECM as I previously thought!! Instead, it’s connected to a relay that can connect/disconnect the fan with the battery directly LOL! I have to say that the electrician who used to work on my babe is a stupid one 😀 . The relay of course is controlled by the coolant sensor and whenever the coolant reaches a specific temperature, it will simply give the relay a signal and thus closes the electric fan circuit with the battery which drops the power from the battery because as we all know, the fan consumes a lot of power and thus the RPM starts bouncing because the ECM is trying to compensate for the loss.

So, I’m trying now to figure out how to re-connect my electric fan correctly to the auxiliary fan relay (which I found in the BMW E36 fuse box layout).

Anyone of you guys can help with this? I need to know what are the colors of the wires that are connected to the electric fan and to the coolant temperature sensor. Some pictures may be good too 😉

BMW E36 Blog: The ultimate BMW E36 M3 information source.

Chris asked me some time ago to write about the Cold Air Intake upgrade and to try to clarify it. I have to admit there is so much talking about it and I couldn’t find any study out there that is supported by numbers. Only opinions of BMW E36 drivers who actually either created their own Cold Air Intake (CAI) or bought a kit to do that.

The idea behind Cold Air Intake (Theory):

The air intake system in your car is where the engine gets oxygen in order to create combustion. When the combustion occurs, your engine will use the resulting energy to generate power. So, if we could feed the engine more oxygen molecules, we should get a better combustion and thus more power. We also know that colder air is denser than warmer air and will thus have more oxygen molecules. So, upgrading the air intake system in your car to get cooler air will, in theory, provide a better combustion and thus more power.

Why People install CAI?

While doing a research about Cold Air Intakes (CAI) and why people normally install them, I’ve found that there are 3 reasons for that:

1. Sound:- The cold air intake will change your engine sound. You can hear the engine whistle in on the intake and you can hear a little deeper exhaust sound too.

2. Performance obviously.

3. Cool looks:- The cold air intake will give your engine a cool look as a performance car instead of a normal BMW.

Does it really work?

Well, this is the hard question for every one who tries to install the cold air intake. In theory, it should work, but in real life there are many factors that may interfere and make the cold air intake update just useless:

1. BMW Engineers are not dump:- If you follow this rule, you will definitely know that your upgrade for the car intake is useless because BMW engineers know what they’re doing and I’m 100% sure that they’re not going to let 5 or 10 more HPs to be lost from your engine just because they don’t want to install a K&N filter. BMW already engineered the air box to keep most of the heat out.

2. The fuel/air management system doesn’t adjust if there is a small change in the temp of the intake air.

3. Cold air is always closer to the ground in the summer so it’s a good idea to make the intake get the air down from the bottom of the front bumper instead of the engine bay.

4. If you decided that you don’t want to get the air like described in point 3 above, you should remember that you will need to create a heat shield to prevent the hot air in the engine bay from reaching to your K&N filter (regardless of where you put it).

As you can see, there are many factors that will cause the CAI upgrade to be useless and thus not to give you the horse power increase that you were wishing for.

Cold Air Intake Brands:

I heard about many cold air intake brands that will look and act great. Some of these are:

1. Cosmos Cold Air Intake: Make sure to get the water shield and the amsoil filter.

2. Umnitza Carbon Fiber Intake.

3. Conforti Cold Air Intake Kit.

If you decided not to buy one of these cold air intake (CAI) kits, then at least go with a K&N Filter. It’s the best choice available. Read here about it (thanks Chris for the reference)

What do I think?

Well, I’m not convinced that you’re going to get any noticeable gain in performance from installing a cold air intake (CAI) kit. There is nothing wrong with the stock paper air filter. It is good enough for other great BMW cars and it’s definitely good enough for your E36. So, I think that the people who actually install it do that for the wrong reasons. I’m not saying that there’s something wrong with getting a nice sound out of your car. It’s your choice after all, but I would recommend getting a cheap air intake and create a heat shield if you’re going to do it anyway. You can invest your 200-400 dollars somewhere else.

If you have a cold air intake…

If you have a cold air intake, lets here your opinion. Did you notice any performance gain after installing it?

BMW E36 Blog: The ultimate BMW E36 M3 information source.