Original Poster. Search My Stuff What's New 3 12 24 BMW timing Chain Issue. Sledger Original Poster 2 posts 49 months. Is the timing chain issue for BMW engines, only for Diesel N47 or have there been any instances of the same issue on petrol engines? I'm looking to buy a 1 series m sport petrol. Allanv 3, posts months. Have a read of this. Still not sure if any petrol 1 series are affected? Can anyone confirm please. Petrol engines such very much from timing chain problems.
The N42 and N46 are worst. N43s are now having probs too. I'll post more info later. Then the N43 think there may be the odd N The N46 had major problems with the timing chain, the tensioner would weaken. If you change it early the only symptom is timing chain noise on cold start. Next failure stage is slipped timing chain, catch it early enough, new tensioner and retime. Worst case is stretched chain, broken guides etc.
BMW timing Chain Issue
A modified tensioner was introduced at this point, these timing chains are more reliable but some as still having problems. My advice is go for a 6 cylinder. This is a i N46 with approx k miles.
Latest tensioner: Edited by helix on Saturday 5th March Mr Tidy 10, posts 79 months. First used in the E46 Compact. Think the N45 was the non valvetronic version.Since the inception of the internal combustion engine, one constant has remained — all of them have a timing chain or timing belt. Most higher-displacement engines have a timing chain as opposed to a timing belt. The chain is located in the front of the motor and is attached to a set of gears and pulleys that power multiple mechanical components, including the crankshaft and camshaft.
In order for your engine to fire, the timing chain must smoothly rotate around the gears without hesitation. Although the timing chain is made out of metal, it is subject to wear and tear and may break if not replaced as recommended by the manufacturer.
The timing chain is comprised of a series of links in the chain — similar to those found on a bicycle chain. The links move on the toothed sprockets which are located on the ends of the crankshaft and camshaft and are responsible for opening and closing valves in the cylinder head and moving pistons and connecting rods in the combustion chamber.
The timing chain can start to stretch and wear over time, which will cause the engine's timing to be inaccurate and produce a few warning signs.
Listed below are 5 of the symptoms of a worn out timing chain.
BMW N42B20 Engine Review
If you notice any of these warning signs, it's advised you contact a local mechanic as soon as possible to diagnose the exact cause and make appropriate repairs as needed.
There are two ways to achieve valve timing in a combustion engine. The first is the two-gear method, which includes the crankshaft to camshaft gear direct connection. This is the method used in most types of heavy equipment and big trucks.
The timing chain method is more common with consumer vehicles and high-performance engines. Over a period of time, the timing chain can stretch, which can cause the chain to skip a gear on the cam or crankshaft.
The engine may also run poorly and lack accelerating power. If this situation occurs, it's likely the timing chain is damaged and needs to be replaced as soon as possible. If the timing chain breaks, the loose metal rolling around inside the motor can lead to serious engine damage. It's recommended by all automotive manufacturers to change the engine oil and filter every 3, to 5, miles. Over time, oil begins to separate as it heats up and is exposed to natural solvents found in gasoline.
If the timing chain begins to wear out, small metal pieces can break off the chain and find their way into the oil pan. When you have your oil changed, and the mechanic tells you there were small pieces of metal inside the oil as it drained or in the filter, it's a good indication that your timing chain is beginning to fail. Metal shavings are also commonly seen when there is extensive wear of cylinder head valves, keepers, retainers and other cylinder head hardware.
A broken timing chain will cause an engine to not start or fail while driving. If it breaks or jumps while driving, the pistons will be damaged from contact with the valves.DOES YOUR BMW HAVE TIMING CHAIN NOISE?! Your engine may be in danger of failing!
The valves themselves will bend and potentially ruin the engine. The check engine light can illuminate for a variety of reasons, one of which could be a failing timing chain. The check engine light may turn on when the onboard computer detects something wrong with the emissions system and engine operation. A stretched timing chain contributes to poor engine performance and increased emissions, triggering the check engine light and the storing of a diagnostic trouble code.
A mechanic will need to inspect the code and prescribe the necessary repairs.The N42B20 engine got all modern system and technology in those days. The engine is based on aluminum cylinder block with cast iron sleeves instead wholly cast iron cylinder block. That makes the engine much lighter than previous inline-four engines from BMW.
There are new 90 mm stroke crankshaft, pistons and connecting rods inside the cylinder block. Engineers made some small changes just to fit them into the new cylinder block. The valve DOHC aluminum cylinder head is on top of the new aluminum cylinder block. That is a big step in improvement because predecessors had 8-valve SOHC heads. The diameter of intake valves is 32 mm; exhaust valve diameter is 29 mm. The engine has variable valve lift system called Valvetronic. The engine has a timing chain.
Both camshafts are equipped with variable valve timing system Double-Vanos. Intake also has electronic controlled variable geometry intake manifold. It is installed for optimized torque and power characteristics at high and low rpm. Besides the engine has the smaller displacement version - 1.
Diesel sound. The timing chain is not very reliable. The noise can be from stretched timing chain or its tensioner. Timing chain life is about 60, miles. Look after radiator condition of the cooling system. After a small overheating the engine will start to consume oil. The reason is susceptible valve stem seals.
Also, you should know that the N42B20 engine has high demands on the quality of the oil. Use engine oil recommended by the manufacturer. The engine is full of modern technologies and electronics. But it also has good longevity and reliability as M40 and M43 series engines. Engine Specs Manufacturer.
BMW Petrol N43 Engine failures - How To Prevent
Production years. Cylinder block material. Cylinder head material. Fuel type. Number of cylinders. Valves per cylinder. Valvetrain layout. Bore, mm. Displacement, cc. Type of internal combustion engine. Compression Ratio. Torque, lb ft. Firing order.N46 is next generation of 4-cylinder inline engines appeared after N42B It was produced on base of N42B20 and seems to have actually no differences in comparison with its predecessor from the first sight. However there are till some differences between BMW N42 and N46 which include new crankshaft, balance shafts and cylinder head cover.
Intake manifold was also renewed and timing chain tensioner was changed. New generators and spark plugs appeared. Valvetronic control block have been additionally integrated into ECU as well as several other slight modifications. New engine used Bosch ME 9. In this engine was modernized. Changed included new intake manifold and exhaust camshaft.
Previous engine control system was replaced by Bosch MV Such engines differ with letter N in their name, for example, N46N. This motor was used in BMW 18i and 20i models. At the same time N46B20 turned out to be a base for designing N46B18 version. This engine was replaced in by new 4-cylinder turbocharged N13B N46B20O0 — is base modification of engine with HP at 6, rpm and Nm at 3, rpm. Engine produces HP at 5, rpm and Nm at 3, rpm. N46B20O1 — is equal to abovementioned version with secondary air injection system.
It produces HP at 6, rpm and Nm at 3,rpm. N46NB20 — is actually the same as HP engine version with new cylinder head cover and exhaust system. At the same time it is equipped by Bosch MV High oil consumption. Reasons for this problem are the same as in BMW N42 and it is mainly connected with usage of low quality motor oil. Drivers need to use oil that is recommended by BMW brand. Otherwise it can lead to malfunctions in valve stem seals and later pistons rings can also go out of order.
Such problem occurs every 30, miles 50, km of mileage. You can get rid of this problem after you have your Vanos variable valve timing system cleaned. Reasons are the same as in N They are connected with timing chain tensioner or stretching timing chain.
It happens after every 60, mileskm of mileage. Pay attention that valve cover gasket may leak every 30, miles 50, km. In this case you need to change it. In some case replacement of vacuum pump may be necessary. If you want to prevent any kinds of problems and malfunctions you only need to use high quality motor oil which is recommended by BMW specialists. At the same time you need to proceed with regular maintenance and examinations of your N46B20 engine.
If you follow these easy tips you are very unlikely to face any problems for a long time. If you want your upgrade to be as efficient as possible you can also buy cold air intake and cat-back performance exhaust system.Top 3 performance modifications for a street driven BMW E A summary of the reliability of the various engines that were offered on Australian market BMW E46 3 series models.
I've been looking at buying an E46 BMW 3 series and have been looking into which engines are reliable and which are not. I'll keep this post updated with any information I find, and welcome any feedback.
It has a timing chain.
Common problems include failure of the mass airflow sensor. N42B20 i, November to Common problems include timing chain jumping teeth usually due to a faulty timing chain tensioner. An updated part is available. This problem has also been known to be caused by a worn or broken timing chain tensioner guide possibly caused by the faulty tensioner allowing the chain to move around a lot more than intendedwhich is a plastic part. Look for rattling noise on start up, although it can be difficult to determine.
You can see if the engine is fitted with an updated timing chain tensioner by the size of the tensioner's hex head. The updated design is the new, clean tensioner in the image below. These engine requires regular oil changes using a good quality synthetic oil. Anything less could cause sludging and contribute to the timing chain problem mentioned above.
Other problem areas include ignition coils, crank case ventilation valve, oil leaks, excessive oil and fuel consumption, and problems with the Valvetronic system. An Internet search for problems on these engines reveals many discussions and a lot of people have had problems which despite being looked at by various BMW dealers and specialists were difficult and expensive to rectify.
It seems this engine was not one of BMW's most reliable. M52 i and i Fitted with timing chain and variable valve timing on both inlet and exhaust valves. Aluminium block which means that it doesn't like overheating and head gasket replacement can result in stripped threads. Some oil consumption problems due to either Nikasil cylinder liningsbore glazing or oil separator valve.Most commonly affecting the 2.
A range of BMW petrol engines in cars registered between to appear to have a design problem affecting the timing chain or tensioner. The engine timing chain is very weak — it stretches over time, and ultimately snaps. When a BMW engine timing chain snaps, the inlet and exhaust valves collide with the pistons, resulting in massive engine damage.
At this point it will bend all 16 valves, shatter the rocker arms, snap and distort both camshafts and the camshaft housing.
Engine Rebuild Process Repairing the severe engine damage is a labour intensive and expensive job. We must remove the entire engine and strip down all engine components to identify and replace all damaged parts. The damaged engine is rebuilt with genuine BMW components including modified chains, guides and tensioners to reduce the risk of a repeat failure.
Each damaged engine is individually assessed — depending on damage to engine parts, and fluctuations in BMW component pricing, the price may be higher. The Watchdog researchers were keen to acquire real-world professional advice on this subject — some of our engine rebuild customers had recommended us to BBC Watchdog as experts in this subject. Some of the BMW owners contacting Watchdog had been quoted huge repair costs from BMW and had instead chosen Prestige to rebuild their badly damaged engines.
You can view their report on the BBC website here:. It is a skilled and time consuming process to correctly repair an engine damaged by a broken timing chain, cheap solutions are unlikely to provide the reliability and warranty offered by Prestige. Iconic One Theme Powered by Wordpress.Original Poster. Search My Stuff What's New 3 12 24 E91 N43B20A timing chain problems? Prev of 2 2 Next. Got Engine Warning light twice. First time it was NOx sensor, second time it disappeared before I could find out what it was.
A thread somewhere suggested looking down the oil filler cap at the chain. Right after running the car there's a lot less, but there it feels like it's too much.
There doesn't really seem to be wear on the top plastic guide though - it's indented, but it looks like it's supposed to be like that. Does anyone know about these engines? Is this a sign of trouble, or are they usually that slack? And no, I didn't buy from a dealer How painful is it to replace the chain? Edited by rabidh on Sunday 14th August If caught early enough you can get away just a new timing chain tensioner.
If the timing has slipped you would need to retime it first. Retiming and changing the chain are both time consuming jobs that require special tools. The tensioner change takes 30 mins tops and no special tools needed.
The timing should not change when just changing the tensioner though I have heard someone managed to muck it up. Great, thanks! I guess if there's no EML then it's less likely the chain has slipped? Is there any way to check easily? I guess I could disconnect the Vanos valves and then check what the cam timings are at their base values via OBD2?