Normal oil and fuel consumption for MkIV Golf 1.4l?

Question

Vehicle:          2002 VW Golf (German)    
Engine:           1.4 liter, gasoline 75 hp   
Odometer:         60k miles / 100k km 
Fuel consumption: 29-33 MPG / 7-8 liters/100km
Oil used:         5W30

I've had to add about 1 liter (1 quart) of oil to my Golf over the last ~1000 miles. Based on my previous experience, this seems quite high. What is the typical oil consumption of this type of vehicle (specs given above)?

The fuel consumption is also a bit higher than I expected for the small engine.

I don't see any oil on the pavement where the car is parked, and the coolant is clean. There is no visible smoke in the exhaust.

On two separate occasions (separated by 4000 km and a few months), the car has begun running rough. Both times the mechanic replaced an ignition coil (different ones) and the associated spark plug.

I was worried that perhaps burning oil was fouling the spark plugs--is this is possibility, or is a succession of failing ignition coils a likely explanation?

Answer 1

Oiled-up plugs usually don't burn out ignition coils, so I'd rule that out unless the plugs get really badly carboned up. Just keep an eye on them.

1l/1000 miles isn't great for oil consumption, but it's not that bad either (although I wouldn't be too happy either given the low mileage of the engine) - have a look at the owners manual as to what the specs are and make sure that you have the correct oil that meets the VW requirements/certification and is of the correct viscosity.

A 2002 Golf isn't exactly a lightweight car, so with the small engine you are working the engine harder in normal driving than the bigger engines, hence the fuel consumption and potentially also the oil consumption.

Answer 2

What burns out the coil packs on many cars is the plugs not being replaced at the proper intervals, so the gap gets so large between the terminals that the coilpack has to generate a much higher voltage spark which then burns out the secondary coil in the transformer of the coilpack. Which is why, after you have replaced the offending coilpack you should either gap all correctly or replace the complete set, otherwise you will have a cascade of the other 3 coilpacks going. A point about the oil consumption, there are mainly three ways where the oil can come out of the engine.

1. Leaking
2. Getting past the oil scraper ring either because the ring set is worn on one or more cylinders or
3. On the overrun; as in the situation where the car is trying to go faster than the engine, going downhill or coming up to a roundabout where you are using the engine to slow down. In this situation if the valve oil seals are weak or worn out, the oil in the valve chest is sucked down the valve stems by the vacuum in the manifold. Smoke only visible on acceleration after the above situation. Get someone to follow you and check.

There may be other reasons but I believe those are the main ones.

Solution..... To 1. Locate and fix To 2. Engine rebuild with cylinders rebored and new rings. To 3. There are ways of replacing these seals without removing the head but that is a specialist job.

The question is if the car is old or high mileage, is it worth it. Get quotes from several garages, don't go for the cheapest, go for the one with best reputation.... Ask around. HTH

Answer 3

On this particular engine, there is a breather pod on the back of the engine block, located below the inlet manifold.

This pod can become blocked and the net result is excessive oil consumption.

Remove the pod and either replace it or clean it thoroughly using something like mentholated spirits or fuel system cleaner.

Access is awkward and you may have more success going in from underneath.

Variations of this breather pod have been fitted to VW groups small block water-cooled engines since the early seventies and cleaning or replacing them almost always leads to a significant improvement in both oil consumption and engine performance.

Coil pack on these engines are notorious for failure and it is very unlikely this has anything to do with the excessive oil consumption. It's worth the expense to source a genuine or Bosch branded coil pack should you have to replace this part again.