Why Does My Car Only Start With Starting Fluid?

If you find that your car only starts with starting fluid but runs fine otherwise, the cause likely has to do with some element of your car’s fuel system.

Fuel Pump Problems

The importance of your car’s fuel pump should be pretty obvious from the name alone. Your car’s fuel pump is the device responsible for sending fuel from your gas tank to your engine. If your fuel pump stops working completely, then your engine will receive no fuel and be unable to run.

If your fuel pump starts to fail, this can lead to issues when trying to start your car, especially during a cold start. When the engine is cold, it needs a slightly richer air/fuel mixture to start, and a failing fuel pump might not be able to deliver enough fuel to properly start the engine in such conditions.

If the issue is being caused by your fuel pump, there are likely to be other symptoms you’ll notice. Your engine might start sputtering or misfiring when you get up to speed, and you might also find it much more difficult to accelerate than you normally would. If your fuel economy starts going way down for no discernible reason, this can also be a sign of a bad fuel pump.

There are a couple of things you can do to test if the problem is indeed being caused by your fuel pump. You can spray a little starter fluid into the throttle body and try starting the engine; if it starts normally at first but then cuts out soon after, this is a pretty good sign that it’s your fuel pump.

You can also try getting someone else to try turning the car on while you listen for the fuel pump. If you listen near the gas tank, you should be able to hear the fuel pump as it starts up. If you can’t hear it at all or if it sounds abnormal, you should get it looked at. 

Leaky Fuel Injectors

Fuel injectors are used to inject fuel into an engine’s combustion chamber. Fuel injectors are necessary to atomize the incoming fuel and deliver it to the combustion chamber as a vapor, for the fuel to be combusted properly.

If your fuel injectors get old and worn out and start leaking, this can be quite serious for your car. Leaky fuel injectors can prevent your car from being able to start normally due to the spark plugs being flooded with fuel.

A serious fuel leak from your fuel injectors can cause serious mechanical problems, so if you think you have one or more leaky injectors, you’ll want to get them fixed as soon as possible.

If fuel leaks into your engine oil, you’ll be left with a problem called “oil thinning” that can result in damaged bearings and scorched cylinder walls. If the leak is severe enough, your engine will be unable to start or will experience hydrolock, resulting in severe internal damage.

Aside from difficulty starting the car, one of the most obvious signs of a leaky fuel injector is the smell of fuel in and around your car. Other indicators include a jerky idle and noticeably lower fuel economy.

Bad Canister Purge Solenoid

A car’s canister purge solenoid is part of its emissions control system. Most modern cars have what’s called an evaporative emissions (EVAP) system, which helps to reduce engine emissions by circulating some of the exhaust gases back into the engine where any remaining fuel particles can be burned. 

The canister purge solenoid is essentially a switch for a valve that allows the exhaust gas to enter the engine at the right time. If the solenoid fails and the valve gets stuck open, however, this can end up causing a vacuum leak that can affect the engine’s performance.

A rough idle is one of the main signs of a failing canister purge solenoid, and in most cases, a bad solenoid will cause the check engine light to turn on. 

Clogged Fuel Filter

All cars come equipped with a fuel filter, which is, of course, used to filter out debris and other unwanted bits from the car’s fuel before it enters the engine. If your fuel filter gets too clogged with crap, however, it can prevent fuel from flowing freely through the filter, which will lead to engine issues.

Many of the symptoms associated with a clogged fuel filter are similar to the symptoms of other fuel-related issues. With a clogged filter, you’ll have trouble starting your car and trouble making power, your engine will be prone to sputtering and misfiring, and you may smell a strong odor of fuel.

Summary

The bottom line is that if your car can’t be started without starting fluid, it’s more than likely an issue with your fuel system. Of course, there are a lot of components in a car’s fuel system, so it’s not always easy to diagnose the specific problem in such a case.

In addition, a lot of these fuel system issues tend to have the same symptoms, so if you’re not a seasoned mechanic, we’d suggest taking your car into the shop if you’re trying to diagnose a problem like this.

Brian