- 2 Min Read
- By: Chris Stovall
Volkswagen VR6 Tips & Maintenance
Volkswagen has a long tradition of innovation. They've always done things slightly differently, from the ground up. One of Volkswagen's most lasting designs is the VR6 engine, which has been used for over two decades, and continues to be used in their current lineup in the Passat, CC, and more. It's a weird engine, with a weird noise, and even weirder engineering.
In the world of automotive engines, there's really not a lot of variation. There's an inline engine, a V engine, and a boxer engine. Volkswagen thought this was not enough, and introduced the VR6 engine in 1992. It's basically the love child of a V6 and an inline 6, and has the benefits of both, while fitting in a much smaller form factor. This means it can be crammed in a car as small as a Golf, but can be powerful enough to power an SUV as large as the Audi Q7.
VW has been using this engine for over 20 years
In a typical V6 engine, the pistons are laid out in a 90 degree angle, with two cylinder heads. The air enters in the center of the V, and exits on the opposite side, towards the outside. In a VR6 engine, the pistons are set at a 10-15° angle, and there is only one cylinder head. This allows airflow to come in from one side and exit the other the same way an inline engine does.
Volkswagen has been using this engine for over twenty years, and it has evolved every model change. The original version was a simple 2.8 liter chain-driven twelve valve motor with Motronic fuel injection and one ignition coil. The current version, in the Q7 and Touareg, is a 3.6 liter, chain-driven, 24 valve, direct-injected, coil-on-plug ignition motor, with over twice the horsepower of the original design.
A thorough service history is a must
These engines are pretty bulletproof. If you're buying one on the second-hand market, there's only a few things to look out for. These engines are chain driven, and over time (around 100-150k), the chains get noisy or stretch. If they stretch, they'll set a fault, and will need to be replaced, which can be a major repair - the chains are on the transmission side. Noisy chains aren't really going to do anything besides make a little chain noise. When it gets really loud, it needs to be addressed, and again - pretty invasive surgery. This seems to be more common on Eurovans and 24-valve models like the R32, in my experience.
As with any European car, a thorough service history is a must. These cars love factory parts and synthetic oil, and have a standard VW service schedule. Spark plugs and filters every 40k, oil changes every 5k, and brake fluid changes every two years, regardless of mileage.
The VR6 only has a few spots where coolant likes to leak out. The thermostat/flange/ECT housing is a very common coolant leak, but are pretty simple to repair. There's a plastic pipe that goes to that housing which has an o-ring on it, that can leak. If you do one, do the other, or you'll need to go back in when the other starts leaking. On the later cars, the engine is designed to run very hot. The coolant hoses can swell up and bloat after a number of years, and should be replaced before they blow up on the road. As with any cooling system repair, proper diagnosis beforehand is a must - and repeat the procedure afterwards for quality control.
Oil leaks are pretty minor on these engines as well. The valve cover gaskets and upper timing covers are the most common areas, but I've seen a few oil coolers leak. These aren't terribly difficult to repair, but if they are severe, they can leak on the exhaust, creating smoke and that "VW" smell.
All in all, the VR6 engine is one of my favorite engines of all time. It's fast, reliable, and makes a noise unlike any other engine I've ever heard. It has a long history with Volkswagen, and I'm excited to see where it goes in the future.
Chris is a journeyman mechanic from Berkeley, California, specializing in late model Volkswagens and Audis. A glutton for punishment, his spare time is spent rebuilding every component of his ’83 Rabbit GTI.