Hi Guys,

Car hesitation and RPM bouncing are the most common problems between the BMW E36 cars. It seems that many cars have the problem and the problem is very hard to fix. I recall that even my previous E30 used to have the problem, but some how, the problem was solved. Maybe with something that I did and didn’t notice it fixed the problem.

Now my E36 318is is having the same symptoms and it gets very annoying especially when I turn my A/C on.

I started looking for a solution to this problem and it seems that cleaning the ICV (Idle Control Value) is one of the most obvious reasons for the problem, so I looked for a DIY about it and found one. The DIY is for M42 engines. I will be writing another post to fix same problem for the M50 engines. Please notice that I didn’t try this DIY myself yet, but I’m going to do it very soon.

Please notice that that cleaning the ICV will not always fix the problem, but it’s a very common reason, so if it didn’t totally solve your car’s problem, then you have other issues, but since the procedure is very simple, I guess everyone should start with it. Please follow the steps below and see if this fixes your car’s RPM bouncing problem. Enjoy

Disclaimer: Use this info at your own risk!! I’m not responsible if this didn’t work for you.

This DIY / write-up will require the following tools/supplies:

Flashlight would be helpful.

11mm socket

Flathead screwdriver

Throttle body (TB) cleaner

OEM hoses if in need of replacement

Throttle body gasket and intake manifold gasket (not technically necessary, but a good idea)

 

It took me about an hour to remove, clean, and put back the ICV. Plus I let the hoses dry (while out of the car) for about 20 minutes on top of that.

 

First, start by opening the hood with the engine off and hopefully not too hot, as you will make contact with the block and the intake manifold.

 

You will take off the intake tube, shown below, by loosening the screws at the blue arrows, and pulling off the hose at the red arrow. Then pull the intake tube off completely.

 

 

Next, you remove the throttle body, by four 11mm bolts. The top two are shown with red arrows below. The bottom two are on the bottom of the TB, in the same position as the top two.

 

 

Move the throttle body off to the side, to gain access to the upper intake manifold, like this:

 

 

Next, we’ll disconnect the hose connecting the manifold to the ICV we wish to remove and clean. Behind the manifold, at the back of the engine bay, is the hose. Just twist it off, as shown by the red arrow.

 

 

Now it’s time to remove the upper intake manifold. Undo all 5 of the 11mm nuts attaching it to the lower manifold. The nut locations are highlighted below with red arrows. The nut in the rear of the engine bay is hard to get to, but a small 11mm socket and 1/4″ drive ratchet should get it out.

 

 

Next, carefully remove the manifold, by slowly lifting it up. I pried it off woodworker style using the backside of a hammer against the block. Be sure to remove it evenly though, lifting it up equally on all sides. Otherwise it will get stuck on the bolts on the manifold’s drivers side. It is easiest to place it as shown:

 

 

Now we have acces to the ICV. As shown below, it is attached with a rubber strap at the point shown with red arrows. The blue arrows indicate the electrical connection, which pulls of when you press down a wire clip. They also point to the hose connections, which you will also want to remove. Note the arrow on top of the ICV. It points TOWARDS the block. The part label with Bosch and the BMW part number written on it also face the front of the car. This is important. You want to put it back facing the correct direction.

 

 

Now, take the ICV and clean it. The image below shows the ports into which the tubes were plugged, and air flows, with a blue arrow. You’ll want to hit it with an old toothbrush and a gratuitous soaking with the TB cleaner. You may choose to clean the throttle body itself while at it with some paper towels and the cleaner.

 

 

Let everything dry, and clean off the hoses if you’d like. One of mine was cracked and therefore replaced, but washing the oil and grease off of them will help them last longer. Replace any that are cracked! They will make your idle worse and allow unfiltered air into the engine = bad. Be sure to let everything dry, especially items that were cleaned with water (hoses.) Installation is the reverse of removal. Be sure to connect ALL the hoses - double check!

 

Are you looking for more do it yourself procedures (DIY) ? I recommend the Bentley BMW 3 series service manual for you. I got it and I think it’s a gold mine for us -BMW E36 Owners-. If you didn’t grab your copy yet, get it right now! I’m sure you’ll find this book worth every penny you’ve paid for. Get the Bentley BMW 3 series service manual

Wait for more from BMW E36 Blog.

Best regards,

Tony Sticks.

Hi Guys,

Oil types make me feel sick because I usually don’t understand them. What weight is better?! operating temperature! thick oils and how this will affect the performance and the age of my engine. Anyway, today I felt like reading about these stuff to make sure I won’t feel sick next time I hear someone talking about this. I think you should read this article because it will definitely add something to your knowledge that you just didn’t learn (well, or hear about before). The article was found here. Thanks Cary for the article (the author).

Disclaimer: Use this info at your own risk!! I’m not responsible for your mistakes man!

1) New BMW’s require synthetic oil. As far as weight, only certain production dates of M3’s and M5’s require the use of Castrol TWS 10w-60.

 

2) The Factory BMW Synth 5w-30 is a version of Castrol TXT Softect sold overseas. A few important things about the BMW oil:

1. It is a Group III hydrocracked oil which cannot be called synthetic in Europe.

2. It is a heavy 30 weight (30 weight can run from 9.3-12.5cst@100c, the BMW oil is about 12.2cst).

3. It is a ACEA A3 oil which means that it is approved for longer change intervals and has a HTHS (High Temperature High Shear) measured at 150c of greater than 3.5.

3) In the US, the only Group IV PAO Synthetics that are available are

1. Mobil 1.

2. Amsoil (but not the Xl-7500).

3. Royal Purple.

4. German Castrol 0w-30 (it has the red label and says on the back, “Made in Germany). Redline is a Group V PolyEster based oil. All other Castrol, Quaker State, Pennzoil, Valvoline “synthetics” are a Group III hydrocracked oil. It is debated how much better Group IV base oils are than group III, but generally they are considered better.

4) When looking for oil for any BMW that does not require Castrol TWS 10w-60, you want to purchase an oil that has either/both of the following ratings:

1. ACEA A3.

2. BMW LL-98 or LL-01.

5) Note that Mobil 1 0w-30, 5w-30, and 10w-30 are NOT ACEA A3 or BMW LL approved oils. This is because they all are thin 30 weight oils (approximately 9.8-10 CST@ 100c) and have HTHS of approximately 3.1. Mobil 1 0w-40 and 15w-50 are A3 rated and the Ow-40 is BMW LL-01 approved. For 99% of climates and users 0w-40 or 5w-40 is the appropriate grade. There are some 0w-30 and 5w-30 oils (like the BMW 5w-30) that are formulated on the heavier end of the 30 weight scale and are accordingly rated A3. These oils will work well also. LOOK FOR THAT ACEA A3 rating. If the oil doesn’t have it, pass on it.

 

6) Some people seem confused about how oil thickness is measured. The first number (0W, 5w, 10w, 15w, etc) is a measurement of how thick the oil is at temperatures of -35c- -20c (depends on the grade). The lower this first number the thinner the oil is at LOW temperatures. The second number (30, 40, 50) refers to oil thickness at 100c (operating temperature). 30 weight can be from 9.3-12.5 cst, 40 weight from 12.6-16.2 cst, 50 weight from 16.3-22cst (approximate). So you can have two oils, one called a 5w-30 (i.e. bmw oil) another 0w-40 (Mobil 1) that are very similar thicknesses at operating temperature. Compare this to Mobil 1 Xw-30 which is close to a 20 weight oil at 100c.

 

7) BMW’s recommended interval of 12,000-15,000 miles is too long. Used oil analysis has shown the BMW oil is generally depleted at 10,000 miles. Running it longer results in excess wear. It is highly recommended that you change your oil once between each BMW recommended interval (approx 7000-7500 miles). If you want to run your oil the BMW recommended interval, I would suggest that you use Mobil 1 0w-40 or Amsoil 5w-40 and change the oil filter at 7500 miles. I would encourage a full oil change at 7500 if you want your engine to last.

 

If you want to spend a few hours learning about oil, go to www.bobistheoilguy.com! But it’s like a different language…. so which one do you suggest if you were going to change your oil?

 

 

Unless you have an M3, in the following order:

 

1. Mobil 1 0w-40.

2. Mobil 1 0w-40, and

3. Mobil 1 0w-40.

 

If you can’t find the 0w-40, the Mobil 1 SUV 5w-40 is a great oil. Can’t find either of these, then go to your dealer and get the BMW 5w-30.

 

The Mobil 1 0w-40 is a great oil, widely available (Walmart, Checker, Kragen, Autozone), and moderately priced. It is factory fill in Mercedes AMG, Porsche, and Austin Martin.

Wait for more from . . . BMW E36 Blog

Best regards,

Tony Sticks.

Hello Guys,

I heard many times about E36 BMWs with VANOS engine and I heard that it’s a very special engine that can boost performance and enhance the overall car responsiveness. But to be honest, I have never read or see that engine in person :-p. Today I did a search for some information regarding this cutie and I found a great article that I thought everyone should read . So as usual, here we go, enjoy and remember to drop me some lines if you have more information about it  that you think is missing in this article.

 

Introduction:

 

VANOS is a combined hydraulic and mechanical camshaft control device managed by the car’s DME engine management system.

The VANOS system is based on an adjustment mechanism that can modify the position of the intake camshaft versus the crankshaft. Double-VANOS adds an adjustment of the intake and outlet camshafts.

 

VANOS operates on the intake camshaft in accordance with engine speed and accelerator pedal position. At the lower end of the engine-speed scale, the intake valves are opened later, which improves idling quality and smoothness. At moderate engine speeds, the intake valves open much earlier, which boosts torque and permits exhaust gas re-circulation inside the combustion chambers, reducing fuel consumption and exhaust emissions. Finally, at high engine speeds, intake valve opening is once again delayed, so that full power can be developed.

 

VANOS significantly enhances emission management, increases output and torque, and offers better idling quality and fuel economy. The latest version of VANOS is double-VANOS, used in the new M3.

VANOS was first introduced in 1992 on the BMW M50 engine used in the 5 Series.

 

 

Here’s how it works:

 

In overhead cam engines, the cams are connected to the crankshaft by either a belt or chain and gears. In BMW VANOS motors there is a chain and some sprockets.

The crankshaft drives a sprocket on the exhaust cam, and the exhaust cam sprocket is bolted to the exhaust cam. A second set of teeth moves a second chain that goes across to the intake cam. The big sprocket on the intake cam is not bolted to the cam, for it has a big hole in the middle. Inside the hole is a helical set of teeth. On the end of the cam is a gear that is also helical on the outside, but it’s too small to connect to the teeth on the inside of the big sprocket. There is a little cup of metal with helical teeth to match the cam on the inside and to match the sprocket on the outside. The V (Variable) in VANOS is due to the helical nature of the teeth. The cup gear is moved by a hydraulic mechanism that works on oil pressure controlled by the DME.

 

 

At idle, the cam timing is retarded. Just off idle, the DME energizes a solenoid which allows oil pressure to move that cup gear to advance the cam 12.5 degrees at midrange, and then at about 5000 rpm, it allows it to come back to the original position. The greater advance causes better cylinder fill at mid rpms for better torque. The noise some people hear is the result of tolerances that make the sprocket wiggle a bit as the cup gear is moved in or out.

 

Double VANOS

 

Double-VANOS (double-variable camshaft control) significantly improves torque since valve timing on both the intake and outlet camshafts are adjusted to the power required from the engine as a function of gas pedal position and engine speed.

 

 

 

On most BMW engines that use a single VANOS, the timing of the intake cam is only changed at two distinct rpm points, while on the double-VANOS system, the timing of the intake and exhaust cams are continuously variable throughout the majority of the rpm range.

With double-VANOS, the opening period of the intake valves are extended by 12 degrees with an increase in valve lift by 0.9 mm.

Double-VANOS requires very high oil pressure in order to adjust the camshafts very quickly and accurately, ensuring better torque at low engine speeds and better power at high speeds. With the amount of un-burnt residual gases being reduced, engine idle is improved. Special engine management control maps for the warm-up phase help the catalytic converter reach operating temperature sooner.

 

Double-VANOS improves low rpm power, flattens the torque curve, and widens the powerband for a given set of camshafts. The double-VANOS engine has a 450 rpm lower torque peak and a 200 rpm higher horsepower peak than single-VANOS, and the torque curve is improved between 1500 - 3800 rpm. At the same time, the torque does not fall off as fast past the horsepower peak.

 

The advantage of double-VANOS is that the system controls the flow of hot exhaust gases into the intake manifold individually for all operating conditions. This is referred to as “internal” exhaust gas re-circulation, allowing very fine dosage of the amount of exhaust gas recycled.

 

While the engine is warming up, VANOS improves the fuel/air mixture and helps to quickly warm up the catalytic converter to its normal operating temperature. When the engine is idling, the system keeps idle speeds smooth and consistent thanks to the reduction of exhaust gas re-circulation to a minimum. Under part load, exhaust gas re-circulation is increased to a much higher level, allowing the engine to run on a wider opening angle of the throttle butterfly in the interest of greater fuel economy. Under full load, the system switches back to a low re-circulation volume providing the cylinders with as much oxygen as possible.

Wait for more from . . . BMW E36 Blog

Best regards,

Tony Sticks.