Tips for Cold Starting a Stubborn Engine


For those living in extremely cold climates, winter can wreak havoc on a pickup truck. It can also showcase some of the truck’s best traits such as being able to cold start in below-freezing conditions.

If you have a relatively new truck, cold starting should not be much of a problem. Most modern trucks such as the RAM 1500 can be started remotely, and they often have a block heater to help warm the engine before turning the key over.

Newer trucks can also be plugged in overnight to keep the engine relatively warm. The difficulty in starting an engine in cold weather typically arises in older model trucks and especially diesel.

A couple of things happen in colder weather that makes starting difficult. One is that the oil in the crankcase thickens. At the same time, battery output often drops in cold weather providing less amperage to turn the engine over. Another issue relates to fuel.

Here are several steps you can take to better ensure your pickup starts right up in cold conditions:

Motor oil

Check the dip stick to see if the oil is goopy. It might be a good idea to consider replacing the oil with a lighter viscosity, something like 10W-30 but not much lighter in conventional oil. You can also switch to CG-4 rated synthetic motor oil. 

Glow plugs

Because diesel engines are inherently difficult to start, they are equipped with glow plugs that heat the combustion chamber before the engine fires up. If your diesel pickup is sluggish getting started even after engaging the plugs, check the resistance using a multi-meter and possibly have them replaced.

Set the choke

In older model trucks – not including diesel engines — there might be a choke handle that you can manually adjust to deliver more fuel to the engine on startup. Even if the truck doesn’t have a manual choke or even a carburetor, it still has an automatic choke. You can open up this automatic choke by pressing the gas pedal all the way down and then raising it about halfway up before starting the engine. You might also need to pump the gas pedal quickly 5-6 times, drawing fuel into the carburetor on especially old pickups. 

Fuel contamination

Diesel fuel is much more susceptible to adverse effects in cold weather than gasoline. The heavier hydrocarbons in diesel fuel can turn to wax when temperatures drop. These wax crystals can form in the water/fuel separator causing blockage. Diesel fuel is also more susceptible to microbes. Check the filter in the separator and possibly replace the fuel.

Water in the fuel

Water can also be a problem getting into the fuel through condensation in cold weather on the inside of the fuel tank. To prevent this, try pulling the pickup into a garage to warm up and apply a “fuel conditioner” additive. You may need to replace the filter in the separator or the fuel completely in the tank.

Other problems

If you are still having trouble starting your truck, it would be a good idea to take it to a mechanic. Unless you are so inclined to investigate yourself, a mechanic will check the fuel injection system, the timing and air intake to be sure everything is working properly.