Former VWDieselParts.com Forum

I've been running 15w-40 in my 1.6 NA Rabbit Pickup. A lot of things need addressing, including a wierdly acting glow plug system (last winter I helped it out with a propane torch) and sometimes leaky fuel pump. But it does start right up when it's above freezing. Now it's below freezing and the battery will barely turn the engine over. I've been keeping the battery inside and warm and charged, so I'm thinking it could be a crappy ground strap (although I did replace all wires and have them clamped to pretty bare metal) or that the two or three year old battery just can't crank it because the oil is thick.

Jack recommends changing to 10w-40 during the winter but according to the online oil charts there isn't that much difference between that and the 15w-40 that I'm currently running. Any thoughts?

clean all your battery and ground connections
I replaced a battery terminal that looked ok but the new one actually made a much better connection.


Of course thinner oil is better in cold conditions or you could just get a bigger battery or a block heater.

I use 5w-40 Delvac ESP in the winter. (Meijer stores currently have a $12 rebate on each gallon.)

And I concur that the starter connections, bushing, and battery should all be up to snuff.

I found green corrosion that had formed inside the insulator of the wire on mine, that was causing a problem starting. I ran 15w40 year round in mine, but thats because I was cheap and it was like 12 bucks a gallon vs synthetic. I replaced a lot of connections on mine on the starter solenoid, battery cables, and alternator wiring because the wiring was just plain poor to begin with, and it made an immense difference. As did getting my starter rebuilt.

I also ran a group 65 battery.

Repeat after me: Check the Ground! Check the Ground! Check the Ground!

Noticed some non-shiny pitted junk inside the ground terminal clamp which I figured might be due to bad surface contact. Put a new clamp on, tightened it up, fired up instantly. Thanks guys!

Cranking the engine for awhile (even if it's not turning over and just clicking as long as the voltage is good), then feeling for hot spots, will always find the bad link in the chain.

i have upgraded wires on my 1.6 engines and run the 15/40 year round. it only gets into the teens at the coldest place i have lived.

that and i use tdi auto starter somebody told me to use and sold to me years ago and it will crank allot at full speed without slowing down. i once had to reprime the fuel system with starter after running out of fuel. not sure if the tdi starter is gear reduction or what. night and day difference between all the old beaters i have come across that will scare you into thinking the car won't start. and i just use whatever replacement battery oreilly and the parts stores say my car uses.