The E36 Series in my opinion is the best 3 Series BMW produced. That being said, E36’s are like any other car in that they need repairs from time to time and there are several major ones that are somewhat unique to the E36 Series. BMW E36 maintenance is certainly more costly than your typical 90’s model vehicle, but I believe you will certainly be pleased at the ease of performing repair work on these vehicles compared with newer models.
I am personally a huge believer in preventive maintenance, and that has saved me from throwing away thousands of dollars on a catastrophic failure. In this article I will discuss the biggest maintenance issues that I have found on the BMW E36.
The first and foremost is the coolant system. The coolant system is the 3 Series Achilles Heel.
Have you ever searched Craigslist for cheap deals on a BMW E36 or E46? If you have, chances are you have seen one listed suspiciously for only around $500. I can bet you that 9 out of 10 times that $500 BMW will say “has a blown head gasket” somewhere in the description.
E36 coolant systems are infamous for the many wear components within them. These vehicles heat up extremely quickly when the coolant system fails. If you drive on an overheated E36 you are at a severe risk of blowing a head gasket and cracking the head. I highly recommend that you rebuild the coolant system every 70-80,000 miles on your BMW. You can pick up the parts typically at around $300-$400.
Coolant system rebuilds aren’t very difficult to perform, I usually can get them done in the space of four to six hours.
It is imperative if you are not sure when the last time coolant parts were replaced that you replace all of the plastic components in one fell swoop.
I made the mistake recently in not replacing the plastic coolant reservoir when I replaced the radiator on my 1996 328i. Two weeks later my brother was driving it on the interstate and the expansion tank imploded. Guess what? Now the car sits in my garage with a blown head gasket.
The radiator on these vehicles has a plastic pipe at the bottom and at the top. The top one cracks more frequently but the bottom will do it as well. There are some upgraded radiators you can buy that are all-aluminum, but if you do not want to spend the extra money just plan to replace the radiator every 80,000 miles or so.
The water pump is an extremely important part on any car and unfortunately it is poorly designed. The pump uses a plastic impeller that circulates the coolant. Unfortunately, the impeller is known to crack and break apart prematurely, sending plastic parts throughout the coolant system and risking an overheated head gasket.
Luckily, you can easily buy an E36 water pump with a metal impeller that is far more reliable. Not even BMW produces those crappy plastic impeller water pumps anymore.
The second bmw e36 maintenance issue I want to discuss is the suspension. E36’s were made from 1990-2000, and because of this whether the vehicle has 40,000 miles or 140,000 miles it should have already had a suspension rebuild. BMW E36 suspensions are first rate, and are universally well regarded as being one of the car’s best features. Like any other vehicle however, rubber bushings fail and bad struts make for a terribly uncomfortable ride.
If an E36 hasn’t had a suspension rebuild by now it probably feels more like a small boat in the ocean than a performance car. E36’s have shocks in the rear and struts in the front. The shocks are extremely easy to replace and the struts are pretty quick as well. Quick tip when buying struts, save yourself a headache and purchase “quick-struts” instead of simply buying the strut and re-using the coil spring.
A few other important things to change on the suspension include: tie rod ends, sway bar links, RTAB’s (Rear Trailing Arm Bushings), and the control arms of course!
Rebuilding suspension components in your E36 will make it feel like your driving a new vehicle. The biggest change I ever noticed in my car was after swapping my blown out struts and RTABs.
Tip: When replacing E36 front struts, go with the “quick-strut” variant instead of purchasing just the strut. The reason being is I had difficulty finding a local mechanic who would compress the strut coil because they said that the coil needed to be compressed significantly more than other cars. I have compressed the coil myself before and I feel that it is extremely dangerous to use the loaner compressor tool from the local auto parts store.
Purchasing the quick strut make the installation go so much faster anyways and contrary to common opinion strut coils DO go bad eventually.
The “marbles in a can” Vanos is really common on BMWs with more than 80-100k miles on them. It’s such a common maintenance item on these vehicles that I can guarantee you will experience a problem with your Vanos unit if you own an E36 long enough.
What Is a Vanos Unit?
It’s just BMW’s fancy term for their variable valve timing unit. Unfortunately BMW used cheap seals in the unit and they tend to break down with time. The most common symptom of Vanos unit failure is a loss of low range torque, and an annoying “marbles in a can” type noise that progressively gets louder as the Vanos seals further deteriorate.
Vanos units are not universal to BMW E36s. They are found only on OBD II E36s, and most of them only have a Vanos unit on the intake camshaft. 98+ models have a dual Vanos unit on the intake and exhaust camshafts.
This is the most difficult maintenance item in the list, as it requires that you play with the timing a little bit. For dedicated Diyers this job can be done in the space of a few hours. This job also requires specialized tools to lock the crankshaft and camshafts in place. I was able to purchase them off Ebay for like 40 bucks.
You will notice an enormous change in your engine after changing out the Vanos unit.
Failure to repair a dysfunctional Vanos unit can cause serious issues for the car. At worst, a bad Vanos can cause the engine to jump timing, at which point you will have to begin a frustrated hunt for a new car. At best, a poorly working Vanos unit decreases the responsiveness of the engine and shrinks it’s low-end power.
If you are planning on replacing your Vanos, Dr.Vanos has an excellent write-up on replacing an E36 Vanos.
Intake ICV & PCV
The last major maintenance items which are frequently overlooked, are the two valves underneath the intake manifold. This would be the ICV and the PCV. These two valves are extremely important for the proper functioning of your vehicle and need to be replaced around the 100-110,000 mile mark.
The ICV typically either gets clogged with carbon deposits or the ICV electric motor seizes. If the idle control valve is clogged with carbon deposits, carb cleaner and a rag will solve the problem. If the electric motor has seized you will need to replace the valve, which typically costs at least $100-$150.
The PCV is the more serious problem. It can fail in several different ways, one of them being that it can create a vacuum that will suck oil into the intake manifold and the engine will then burn it off. It’s best to go ahead and swap the PCV plastic hose with the PCV. The plastic hose runs from the valve cover to the PCV, and you will find that it clogs up with old oil and breaks down overtime.
Both of these valves can be replaced without removing the intake manifold, and can be swapped in under an hour.
These two valves are not difficult to replace and will help ensure the longevity of your engine performance.
Valve Cover Gasket
Honestly, valve cover gaskets go bad on any car. However, I do feel like and others have noticed that E36 valve cover gaskets tend to need replacement at a fairly more frequent interval than many other cars.
The two obvious symptoms of a bad valve cover gasket are a burning oil smell and if you are changing the spark plugs and you see a pool of oil inside.
The burning smell will originate from oil leaking out of the gasket and dripping on to the exhaust manifold. If you can smell the burning oil you should be able to pop the hood and see smoke coming from the exhaust manifold. At that point you need to shut off the car and wait until you replace the gasket because the burning oil can cause a fire.
The oil in the spark plug tubes comes from a leaky spark plug tube seal. Technically this is not part of the outer valve cover gasket, but the gasket usually comes with the tube seals included.
That’s it for the most common bmw e36 maintenance issues. For the most part the rest of the maintenance I have had to perform on E36’s has been odds and ends. Spark plugs, alternator, battery, window motors, and power seat gearboxes. Overall, these cars are very reliable as long as you take care of these major issues when the time comes.