Truck Won’t Start: Tips and Tricks to Avoid Calling the Tow Truck
You turn the key and you get that sickening feeling in your stomach. Your truck won’t start.
Maybe it’s making that maddening click-click-click noise, like it has a dead battery. Or even worse, it spins over but doesn’t start. Does it sound like it’s out of gas, even though the gas gauge shows a full tank? Or is it spinning over, but then making strange mechanical noises, like the engine doesn’t have any compression?
None of these scenarios are good, but don’t panic. Let’s go through some basic things you can do yourself to see why your truck won’t start. Often a simple fix will get you back on the road fast, and you can avoid calling a tow truck.
The Dreaded Click-Click-Click Noise
Contrary to popular belief, promising your truck that you will buy it a new battery if it will start for you “one more time” has no effect. Sorry, but making promises to your truck will not convince it to start. It wants to see more effort on your part first.
When you turn the key and hear the click-click-click sound we all know to well, your battery is dead. So your truck won’t start because it doesn’t have enough power to fully energize the electromagnet inside the starter solenoid. The magnetic field keeps on failing, so the solenoid spring keeps on snapping back. That’s what is making the click-click-click noise you hear. Don’t make the common mistake of replacing the solenoid.
Turn your headlights on and switch them to high beam. Do they shine brightly and stay bright after about 15 seconds? If yes, leave them on and turn the key again. Sometimes the extra current draw of headlights through a poor battery terminal connection will make the engine start. Try it. You might get lucky. If it does start, make plans to clean those battery terminals soon.
If instead the headlights immediately dim when you turn the key it means the battery is dead. Try jump starting it. Wear safety goggles, because batteries can explode and will blow acid and plastic shrapnel at you with great force.
However, if the headlights continue to burn brightly as you turn the key to start and it still doesn’t start, you have a problem in the electrical feed to the starter. Possibly you have a bad solenoid or a bad starter motor. But don’t give up just yet, there’s one more trick.
If you can see the starter motor, tap on it firmly, but not with deadly force. Then try turning the key again. If still no luck, you can have somebody hold the key on start while you tap on the starter. Many times, that will jar a bad starter motor loose and make it start the engine. It’s worth a shot, right?
Fuel Pump Problems
Let’s say that when your truck won’t start it turns over normally but doesn’t start, and the gas gauge shows enough fuel is in the tank. What to do?
When you first turn the key can you hear the electric fuel pump inside the gas tank come on and run for three to five seconds? If not, then listen closely near the fuel filler cap as somebody else turns the key from off to run, but not all the way to start. If you still can’t hear the fuel pump activate, here’s something you can try. It’s not exactly DIY vehicle maintenance, but it might get the job done.
Get a rubber mallet and bang sharply on the bottom of the fuel tank as your helper cranks the engine over. Many times, the banging will jar a stuck fuel pump loose and make it run.
Obviously, you want to be sure the truck is in park (in neutral for a standard transmission), the parking brake is on, and that your helper has his foot on the brakes. Don’t get run over by your own truck.
If you still can’t hear a discernible humming noise from the fuel pump, it may be a bad fuel pump relay or a bad fuse. Locate the fuel pump relay inside the fuse box and replace it with a good one. Make sure you know it’s a good one, too.
Where can you find a known good relay at a time like this? Perhaps you might take one from the windshield wipers.
If no luck, locate the fuses that say Fuel Pump, PCM or ECM. You will find several. Check them all, and if you find a bad one, substitute it with a known good fuse from an accessory with the same capacity fuse. Do not insert a fuse with a higher rating.
The reason for checking fuses is that the PCM (ECM in some trucks) powers the fuel pump relay, and that particular circuit within the PCM has a separate fuse that powers it. This is one of those things that takes less time to do than it takes to explain.
Can You Smell Gasoline Near the Engine?
OK, suppose that after doing all this and still your truck won’t start, but you smell a strong gasoline odor near the engine. It means the problem is not lack of fuel. Suspect lack of spark.
Many things will cause that on a modern truck with fuel injection and electronic ignition, as those two systems share some common data sources like the crankshaft position sensor and a camshaft position sensor. Trouble shooting can be involved, so all a novice can reasonably do is locate all the fuses that power the ECM and check them all. Hope you find a bad one.
If the engine turns over too fast like it has no compression, it has mechanical damage. Most commonly a timing belt that has broken or a timing chain that has slipped. Either one is very involved to check and repair.
Here’s one last tip. If the engine was running perfectly last time you drove it, suspect a bad timing belt.
When you turn an engine off, as it approaches its final stopping point it will turn backwards a few degrees from hitting engine compression. If you have a worn-out timing belt, that backwards motion can shear off a few belt teeth, causing your truck not to start next time.
If that’s your problem, look at the bright side. You were past due for a timing belt replacement anyway, so now you have to do it.