DEF Heater Failure
DEF heater failure is a common problem that affects most 2010 and newer Mercedes-Benz Sprinters.
The AdBlue tank has a heater in it to keep the DEF from freezing. The heater element burns out, which causes the check engine light to come on and limp mode.
This may not be a problem in the summer, but it will allow DEF to freeze in colder climates and winter months. If ignored, it will lead to an active start countdown being initiated.
Broken exhaust flex pipe.
This is a common problem for the 2007 or the 906 chassis with the V6 OM642 diesel engine. In the 2007, 2008, 2009 model years, this is part of the catalytic converter.
On the 2010 and newer models, this is part of the Diesel Particular Filter.
Exhaust leaks from the flex pipe can melt wiring nearby, causing the engine to shut off, not restart, and start the counter.
No Start Count Down.
Sprinter vans 2010 model and above with “Bluetec” will start counting down remaining start cycles if any of these conditions are met: if there is an issue with the DEF Adblue system.
If DEF level is not monitored and runs out, or Nox sensors failure or any other components failure related to DEF/Adblue system fail.
Once the countdown is started, it is strongly advised to get your sprinter diagnosed before it gets to the last few remaining starts cyles.
Sprinter’s Diesel Particular Filter (DPF) captures soot from the exhaust, so you do not see black smoke puffing out of the exhaust. DPF accumulates soot until it reaches a level to do what is known as regeneration.
During regeneration, the ECU causes the DPF to reach a very high temperature of around 1,200F, incinerating the soot. Keep in mind that ash will build up inside the DPF and not be burned out if incorrect engine oil is used.
The DPF can clogs up and restricts exhaust flow. If ash content is too high, one option is to force DPF regeneration with SDS Start Scanner manually. If manual regeneration fails, the only option is to replace the DPF.
Problems that can prevent DPF regeneration include:
- faulty temperature sensor,
- swirl flap motor,
- EGR valve,
- running issue keeps the DPF from doing its regeneration.
If not corrected, the exhaust will have a severe restriction. The van will lose power as it clogs up further.
Reduced power / limp mode.
A Limp Mode is a safety feature in Sprinter that protects the engine from damage. It may be activated if you push the engine too hard to the limit. When MIL illuminates or Check Engine Light is flashing on your dashboard, that is an indicator of Limp Mode.
It tries to lower engine power to prevent further damage to affected components. The onboard computer or ECU would switch the turbo off to reduce power, forcing the owner to get the van to the Sprinter shop and have it serviced.
Limp mode is generally caused by faulty EGR, faulty oxygen sensor, swirl flap motor, intercooler hoses leaking, actuator, resonator, etc.
Oil Cooler Leaks
Sprinter oil cooler leaks are common on the 2007-present models with the OM642 V6 engine. The oil cooler seals are where most of the engine oil leaks occur.
Mercedes has updated the seals to much better material made from Viton, which increases their life. Because it’s difficult to reach the location, the oil cooler is an expensive repair. The turbocharger, intake manifold & more have to be removed to gain access to it.
Glow Plug Issues
As with any diesel engine, the glow plugs & modules in Sprinter do not last forever. Also, sometimes the stubborn plugs will break off in the cylinder head.
We have the special tools to drill out & extract the glow plug without removing the cylinder head in most cases. Pricing varies on glow plugs depending on engine & year.
Injector Issue / “Black Death“
An additional typical problem is usually called “black death. “ The copper seal ring, which is located middle of the injector and cylinder head, deteriorates and makes it possible for combustion gasses to escape. As a result, black tar and coal-like black material would accumulate over fuel injectors.
The replacement or removal of injectors mostly causes it if copper seals are not replaced by new ones or seals incorrectly installed. This allows the combustion gasses to leakage over overtime. Depending on the seriousness, you might scent an unusual exhaust/fuel odor when the engine runs and even hears it puff.
Depending upon the seriousness, it can need tons of time to break down and loosen up this "black death" build-up accumulation and secure injector to change the seal. Sometimes the injector and cylinder head has to be taken off to obliterate the tar.
Noise from the Torque Converter
This “Rumble” Torque converter noise can be resulting from a few things, which include wrong transmission fluid oil or lack of fluid level, etc., but the most expensive fault is when the lock-up clutch of Torque Converter wears out.
This issue can affect any Sprinter (except 4 cylinder engines). The fix is costly because the transmission would need to be pulled down, and the Torque Converter needs to be rebuilt. Then transmission and the torque converter need to be reinstalled.
Frequently Asked Questions
Are our Sprinter vans expensive to maintain?
- Mercedes Benz Sprinter's fatal flaw is directly related to the components involved with their exhaust system. The cost of maintaining and repairing these vehicles is a staggering average of ten cents per mile.
What is a Glowplug?
- A glowplug is an electrical pre-heating device used in a diesel engine to warm up the fuel before ignition. This is very important in cold weather and climate since glowplugs should heat diesel to a pre-defined temperature before igniting. The timing and duration of glowplug duty are determined and commanded by a glow plug controller /timer.
What is DEP?
- Diesel Exhaust Fluid is a non-hazardous solution consisting of 32.5% urea and 67.5% de-ionized water. DEF is sprayed into the exhaust stream of diesel vehicles to break down dangerous NOx emissions into harmless nitrogen and water.
What is DPF?
- Diesel Particulate Filter - is a pollution control device commonly connected in Diesel Engines which filters particulates from the exhaust and burns them off during regeneration. There are two types of DPF; the common mode is the Active; the car's ECU / ECM controls regeneration; the other is Passive.
How many miles will a Mercedes Sprinter last?
- Sprinter will easily see a lifespan of over 300,000 miles. As long as you stay on top of regular maintenance, the longevity of a Mercedes Sprinter will serve you well. But these vans are not devoid of some major common issues, and these problems are expensive to repair.