Sprinter Turbo Issues

Jul 19th 2023

Sprinter Turbo Issues

The Dodge, Freightliner and Mercedes Sprinter van has become ubiquitous. While repair and diagnostic resources are available, these are still Mercedes vans, and slightly more complex than the Chevy Express and Ford Econoline vans they may have replaced. As you can tell from just looking at the front of one of these vans, space and access under the hood comes at a premium, although that was also the case for the “doghouse” vans from the big 3 as well. Extra frustration comes from the fact that many of these issues can throw your van into a reduced-power “Limp Mode” – this will let you pull the van off to the side of the road, onto a tow truck and around the dealer lot, but make it too slow and underpowered to keep driving on public roads – you know, sort of like the turbo isn’t making any boost, making that an logical starting point for your diagnosis. The only thing slower than a fully loaded cargo van with a diesel 5-cylinder is a fully loaded cargo van with a non-turbo diesel 5-cylinder.

There are a lot of common issues on the Sprinter van that could point to the general area of the turbo, without having to replace the turbo itself. Two of the most common Sprinter-specific turbo issues only occur when the engine is under heavy load, making it a lot harder to figure out when the van is idling in your driveway. But much like any other turbocharged vehicle, the key to reliability is a strict maintenance schedule. A reliable supply of clean, pressurized oil is critical to ensuring turbocharger reliability – when in doubt, err on the side of caution and change it earlier rather than later. The center bearing in your turbo can spin at 200,000 RPM or more, and a momentary lapse in oil pressure can be enough for that bearing to run dry and overheat, which can lead to excessive shaft play or even breaking the shaft. Being proactive about replacing your air filter helps too, keeping debris from entering your intake tract and damaging the compressor wheel on the turbocharger (Garrett now offers a replacement turbo for early 3.0L models with a billet compressor wheel for better durability, as well as slightly better throttle response). On the opposite side of that coin, a clogged air filter can restrict airflow to the intake, resulting in a pressure imbalance that can cause the turbo to leak oil into the compressor housing. EGR is a controversial topic in diesel enthusiast circles, but EGR valves and coolers can be cleaned while the van is down for other service work, to prevent it from becoming an issue while you’re en route to the next job or campsite.

Aside from the things that apply to any turbocharged vehicle, there are two common issues that affect Sprinter vans at a higher rate than other vehicles:

Sprinter Turbo Resonator

Sprinter vans with the 2.7L 5-cylinder diesel (engine code OM617) have what’s called a “turbocharger resonator” on the intake side of the turbo. This is an injection-molded plastic piece designed to reduce turbocharger noise or “whine”, though the heat and vibration inherent in where it is located under the hood means this can split open at the seam – usually caused by a spike of air pressure inside the intake tract, which would happen if you were to, say, floor it merging into traffic, spooling up the turbo and making boost in order to make that move. This is the kind of failure that happens suddenly without prior warning, and usually at an inopportune moment. There have been revisions to this design, but even the latest part from a Mercedes dealer is still an injection-molded plastic piece, which may be sturdier than the original design from the early 2000’s, but still not a great place to use such a cheaply-made and fragile part.

Several companies now make a resonator delete kit to eliminate this potential failure point before it leaves you stranded. The resonator delete kit replaces this plastic piece with an aluminum one, can usually be found online for under $100 and advertises a 20 minute install time, but of course that depends on your DIY level and whatever else you find or replace when you dig into the van. The (allegedly) easy installation makes this a natural starting point to check if your 2.7L Sprinter goes into limp mode, or even something you might want to do preventatively before the plastic piece ruins your day at some point in the future. The big tradeoff is that you will get more noise from the turbo, but hey, some people like that and pay a lot more than $100 to enhance it in their vehicle.

Charge Pipes & Intercooler Hoses

“Charge Pipes” is the technical term the dealer parts counter would refer to them by, but they’re more colloquially known as the intercooler hoses because – get this – they’re the hoses that connect to either end of the intercooler. These aren’t as Sprinter-specific as the resonator is, but they are an extremely common failure point on 2007-2009 Sprinter 3.0L models. The turbo-to-intercooler hose in particular has a habit of developing cracks on the inside of the bends that are frustratingly difficult to spot when you’re poking around under the hood with the van idling. Spraying the hoses down with soapy water can help you find leaks, but it’s still hard to get the leaks to show themselves in the driveway. You can have someone rev the engine while you look under the hood, but that doesn’t quite simulate the engine coming under load when you are merging onto the freeway or driving up a steep hill.

The 2010 “BlueTec” refresh included new charge pipes that can be backdated to 2007-2009 models, and by the time you’re reading this post, it’s likely that premature charge pipe failure on these vans is similar to the biodegradable wiring harness on 90’s Mercedes models – if the vehicle is still on the road today, it’s probably already been fixed. Still, this is worth checking on your Sprinter or any other turbocharged vehicle experiencing a low boost condition, as well as replacing at the same time as the turbo itself (if you end up having to do that).

Oil Cooler Leaks

This is specifically not a turbo issue, but the oil cooler lines on the 3.0L diesel V6 pass right underneath the turbo, and leaks from them are often incorrectly attributed to the turbocharger. Unfortunately, unlike the two other issues, there isn’t an easy solution to this one – you’ll likely have to disassemble a bit of the van to get to that area and find and cure the exact cause of the oil leak. But it is worth noting that a turbocharger oil leak would usually be accompanied by noise, maybe a slight power loss, and other symptoms of a bad turbo – any oil leaking from the turbocharger itself, and not the oil cooler line or oil return line fittings, is oil that isn’t going to that turbocharger’s center bearing, and therefore causing its own damage. If your diagnostic process ends with you needing to replace the turbocharger, we recommend replacing those oil cooler lines at the same time to prevent that repair bill in the future.

Another oil leak frequently misattributed to the turbo is one from the engine’s air/oil separator valve, part of the PCV (Positive Crankcase Ventilation) system that routes excess air pressure from inside the engine back into the intake tract. With age, that valve can leak oil into the intake, which will naturally make its way through the turbo and into the charge pipes, making it look like the turbo itself is leaking oil into the intake. PCV issues can cause turbocharger oil leaks on any vehicle, but this is another issue exacerbated by the tight packaging of the Sprinter’s engine bay.

Of course there are other signs of turbo failure (excessive noise or oil consumption, power loss, and any number of check engine light codes), but these are the issues that are specifically related to a design or production flaw on the Sprinter’s powertrain – all the other signs also apply to any other turbocharged vehicle. If you do end up needing to replace the turbocharger, we would advise replacing the resonator on a 2.7L van, oil cooler lines and fittings on a 3.0L, and the charge pipes on any flavor of Sprinter.

In addition to these turbo issues, there are other turbo-adjacent issues to worry about, like exhaust flex pipes that can come apart with age, and EGR that can clog up. Newer vans have selective catalyst reduction (SCR), diesel particulate filters (DPF) and diesel exhaust fluid (DEF) injection systems that make notoriously dirty diesel exhaust a little more palatable for the people driving behind you or walking on the sidewalks you drive past. Seeing as though these systems mostly apply to the exhaust system past any traditional engine management controls, you could (in theory) drive around with these systems inoperative. But the ECU knows when those systems don’t work, and when they don’t affect drivability in a strictly mechanical sense, they can shut down operation in other ways, like the aforementioned limp mode or even a notice on the dash that lets you know you can only start the engine X number of times before the ECU shuts everything down and you’re forced to tow it into the shop.

We’d love to sell you a replacement turbo if you do need it, and we have another blog post all about finding the correct replacement option for various Sprinter models. And maybe this is a little self-serving, but we also don’t want to field upset phone calls from people who think they got a defective turbo because the replacement did not fix their issue. So take an extra look before throwing needless money at the problem, and if you find out that you do need a turbo, then look up your van on our website and see what we have available: we carry OEM replacements from Garrett, BorgWarner and IHI, Factory Turbochargers aftermarket replacements that fit like OEM and include the gaskets and a 3 year warranty, as well as other options for any Sprinter, Mercedes diesel or anything else with a turbo.