In theory, it was a good idea. Two major companies, BMW and France’s PSA (Peugeot/Citroen), teamed up to jointly develop a high-volume, turbocharged gasoline engine. No wonder: this way of doing things allows them to reduce design costs as well as share expertise and technology.
The new engine debuted in 2006 under the hood of the Mini Cooper S (the British brand belongs to BMW), and since July 2006 it has been present in most PSA models. The power unit was awarded the title of “Engine of the Year” in the category from 1.4 to 1.8 liters, which did not give for a long time!
The jury appreciated not only the advanced technology (high power from a small volume, twin-scroll turbine, Vanos variable valve timing system, direct injection and smart cooling system pump), but also the good balance between performance and average fuel consumption.
However, alarming reports of problems with the 1.6 THP soon began to emerge. The first questions arose about a defective chain tensioner. Signs of the fault: noisy engine operation (clunking) during the first minutes of operation after start-up. After warming up, the unpleasant noise usually disappeared. In extreme cases (which are quite a lot) the chain after 40-50 thousand kilometers stretched to the size of a whole link!
There are also premature wear of camshafts. The result? Expensive repair of the head. Unfortunately, repair often gave only a temporary effect. Soon the fault would reappear.
Another problem with the 1.6 TNR engine is a sudden dip in traction. The causes are several. Problems with the software controlling the operation of the power unit, or the departure of gas distribution phases due to chain stretching. In addition, the stretched timing chain can jump a few teeth. Sometimes the control unit goes into emergency mode, having detected an incorrect mixture composition. In this case, the display will show a faulty exhaust system.
Among other things, it is necessary to regularly monitor the oil level – some copies are able to consume up to half a liter per 1000 km. However, light smoke from the exhaust pipe is a normal phenomenon for engines with direct fuel injection.
In 2010, a modernized version of the motor, complying with Euro-5 standard, appeared on the market. Timing elements were strengthened and the power of most modifications was increased. But, unfortunately, the problems with the chain tensioner have not completely disappeared. Nevertheless, it is worth recognizing that the number of malfunctions has significantly decreased.
And, still, the French-German gasoline motor is well suited for everyday use. It is dynamic (provided that it is used in cars weighing less than 1.5 tons), sounds pleasantly and impresses with its elasticity (high torque is available in a wide range of revolutions).
A few words should be devoted to economy. To achieve the promised result of 6 liters/100 km, you need to be very careful with the gas pedal. In order to use the full potential of the engine, you will have to fill up with 98-ym and consider the consumption at the level of 14-15 l/100 km.
The engine family (1.6 TNR and its non-inflated version VTi) has been available on the market for a long time. Therefore, there will be no problems with the search for spare parts and repair in independent services. Official workshops should be avoided, especially by Mini and BMW owners, as the prices in BMW services are very high. It is worth noting that in non-inflated engine modifications, timing problems occur less often.
The manufacturer is still working on increasing the service life of individual elements of the powertrain. Therefore, the tensioner on the 2012 motor will be stronger, already modernized in 2010. The cost of replacing the timing chain with a tensioner and two guides in a normal service will require no more than 400-500 dollars. Mechanics recommend using a substitute of the brand “Febi Bilstein”. The cost of the set from 100 dollars.
Typical faults EP6/EP6DT, N12-16
On many even quite “young” Peugeot and Citroen EP6 motors work unstable and noisy, do not develop the required power, “choke” when accelerating, consume too much fuel and oil. After a relatively small mileage, the timing phases “run away”, the “antipollution system faulty” error lights up on the dashboard… On an almost new car, the coolant temperature sensor can “glitch”, which leads to improper operation of the motor and replacement of the thermostat. Frequent oil leaks add their own drop of tar. The main potentially dangerous places are valve cover gasket (especially if oil leaks into spark plug wells and eats ignition coil tips) and oil filter housing, vacuum pump gasket, electric oil pump valve.
EP6 engines like frequent oil changes, and not just any oil, but 5w30 Eneos from Total, like good gasoline and regular oil level checks. The engine should be regularly inspected and oil leaks should be eliminated in time. And turbocharged EP6DT engines also like to be periodically given a proper “run”, among other things. Buying a car with EP6DT turbo engine, be prepared for the fact that by 50 thousand surprises are possible.
Valve lift mechanism
The EP6/EP6DT, N12-16 engines use a proprietary Bavarian system for controlling the stroke of intake valves. It is called Valvetronic. The intake valve lift control allows to dose the working mixture entering the cylinders, which allows to increase the engine economy without loss of power. This unit, of course, complicates the engine design and is a source of specific problems. When oil changes are infrequent, and especially when running an EP6 engine with a low oil level, the valve lift mechanism fails. There are options here. Either the motor itself, which moves the valve lift shaft, breaks, or the worm pair of the motor with the shaft mechanically wears out.
Turbocharger
Symptoms: lack of power, smoke from the exhaust pipe, loud whistling when accelerating.
A common problem with EP6DT turbo engines is a clogged tube that feeds oil to the turbo, clogged with the same old oil deposits. When the oil stops flowing to the turbo, the turbo will shut down. There are cases of rotor wear after low mileage. Repair is expensive, especially in powerful modifications.
TNVD
Another “generic sore” EP6DT – frequently arising problems associated with combustion skipping in the cylinders. The computer shows a whole bunch of errors – p1336, p1337, p1338, p1339, p1340. To them are often added and errors p0087 (low pressure in the ramp), and p0313 (mixture ignition misses because of it). When the engine warms up, some injector is disabled.
No matter how much you would like, you can’t write off everything to bad gasoline in this case. The mystery, as a rule, lies in a faulty fuel pump (high-pressure fuel pump). If your pump can no longer pump normally, combustion lapses appear in the cylinders, the car loses traction, there are frightening dips at high speeds, the candles are covered with a whitish coating characteristic of a poor mixture.
Vacuum pump
Symptoms: failure of the brake booster. The pedal becomes “tight”. For braking, it is necessary to apply considerable force.
Repair will not be excessively expensive, but only if it is possible to purchase substitutes of high quality. Specialists advise the product of the brand “Pierburg”. The cost of the amplifier from 70 dollars, plus work. In the official service for everything will have to give much more.
GRM phase displacement
As for problems with the phases of the timing, first of all, it is necessary to correctly identify the source of the problem. And further – either replacement of the chain with tensioner and calipers, or replacement of the “stars” phase adjusters camshafts or valves that supply oil to them, or cleaning of oil channels in the cylinder-head, or all of the above at once. The mechanism of valve lifting or worn out camshaft beds can also drink blood. It should be noted that in a multi-brand service you are unlikely to repair or adjust EP6 and EP6DT motors normally. Almost any intervention in the engine requires subsequent adaptation with the help of a computer and specialized software. Lexia is not available in every car service center. There are even fewer people who know how to use it properly.
Of course, the first thing to do is to check the oil level! EP6 engine because of its complex timing system is very sensitive to oil level and “shakes” if there is not enough “just a liter”. More often than not, the timing is shifted simply because of a stretched chain. No wonder: the EP6 motor chain is hardly thicker than a bicycle chain.
Timing chain
Symptoms: metallic noise in the area of the timing chain. Most often heard within a few seconds after starting a cold engine.
A single-row timing chain has a short life. It simply stretches. Add here recommended in due time by the French oil changes in 20000 kilometers and just by the end of the warranty period you will get a black substance blackened motor, stretched chain and displaced phases. The oil channels in the cylinder-head and the valves of the phasoregulators, which supply oil to the phasoregulators, are clogged with slag from rarely changed oil. The oil sludge can also damage the phasoregulators themselves. On the engines of the first releases metal sealing rings of camshafts “saw through” the tracks on the camshaft beds, because of what again the necessary oil pressure is not supplied to the phasoregulators. The engine starts to “rich” and error P2178 appears.
Mechanical wear of this engine’s fuel injector can even lead to the breakage of the timing chain, because the pump is driven by the intake camshaft.
Valve fouling
EP6 valves are covered with thick soot, especially on turbocharged engines. This is primarily due to the rapid wear of the oil sealing caps, especially on the exhaust valves. The exhaust valves get hotter and the caps on them die faster. Oil flies into the cylinders, its combustion products settle with greasy black growths on the valves, prematurely disable the catalytic converter. Soot impedes the normal operation of valves and worsens gas distribution, but also additionally “rubs” and already bad oil caps, from which the latter completely cease to fulfill their function. In order to eliminate the soot on the valves, it is necessary to act radically, cleaning the valves manually.
Before the process has not gone that far, you can preventively change the oil caps without removing the cylinder-head. This is not particularly expensive, and should be done if your EP6 has run over 50,000 miles and has started to eat oil. Oil consumption, as a rule, is also associated with a torn oil separator membrane, which is located in the valve cover. In this case, do not bother with Chinese repair kits, they are just terrible quality, and it is better to change the whole cover. We always have original ones in stock.
Firmware
Symptoms: the car becomes sleepy, the engine reacts rather reluctantly to adding gas, error messages appear.
The reason is a miscalculation of the engine management program. Sometimes an update helps. If the computer detects an incorrect composition of the mixture (bad gasoline or the departure of gas distribution phases), it will limit the engine power and issue a message about the malfunction of the exhaust gas cleaning system.
Distributor shafts
Symptoms: uneven engine performance, check engine light illuminates.
Too long a period of operation with minimum oil level leads to rapid wear of the shafts and liners. It will be necessary to overhaul the engine, including a complex head. The cost of correcting the problem can be significant, so careful monitoring of the oil level is essential. The manufacturer recommends oil grades with viscosity 0W-40 and 5W-30 (the best choice).
Collectors
Symptoms: exhaust odor in the cabin, noisy engine operation.
Sometimes there are cases of cracking of the exhaust and intake manifold. You can not count on analogs. But you can find used ones. For the intake manifold will ask about 60 dollars, for the exhaust manifold – about 50 dollars.