Why is my Subaru Impreza not starting?
The most common reasons are a dead or dying battery, a failing starter, or a fault in the fuel or ignition system. Start by testing the battery voltage and listening for cranking, then rule out the immobilizer, fuses, and fuel delivery before seeking professional help.
Common starting problems to investigate
This overview covers the main systems that can prevent your Impreza from starting and how to assess them quickly.
- Battery and charging system: a dead, discharged, or corroded battery can prevent the engine from turning over or cause it to crank slowly.
- Starter motor or solenoid: a worn starter may click or fail to engage, leaving you with no crank.
- Ignition switch or ignition coil/coil packs: failure here can stop spark and fuel from igniting the air-fuel mix.
- Immobilizer/anti-theft system: a malfunctioning key or immobilizer can prevent the engine from starting; look for a blinking key icon on the dash.
- Fuel delivery problems: a empty tank, failing fuel pump, clogged filter, or pressure loss can prevent starting even when the battery turns the engine.
- Electrical fuses and relays: a blown fuse or faulty starter relay can interrupt power to the starter or fuel pump.
- Engine sensors: crankshaft position or camshaft position sensors, among others, can cause a no-start if the ECU cannot determine timing.
- Transmission/neutral safety: automatic transmissions require Park/Neutral to start; manual cars rely on the clutch switch.
- Engine mechanical issues: timing belt/chain problems or severe internal damage can prevent starting or cause a no-start condition.
Addressing these areas can narrow down the cause, but some issues, especially those involving the immobilizer, fuel pump, or internal engine timing, may require professional diagnosis.
Step-by-step checks you can perform safely at home
Use these checks to diagnose common no-start symptoms and decide when to call a tow truck or a mechanic.
- Check the battery: measure voltage with a multimeter; a healthy resting battery should read about 12.6 volts or higher. If it’s below 12.0 volts or rapidly drops when you try to start, charge or replace the battery.
- Inspect battery terminals: look for corrosion, loose clamps, or damaged cables; clean and tighten as needed.
- Listen for sounds: a single click often points to a starter relay or battery issue, while a rapid series of clicks can indicate insufficient battery power.
- Check dash lights and immobilizer indicator: if the dash lights are very dim or the immobilizer/key icon blinks, the key may not be recognized; you may need a new key battery or to reprogram.
- Check fuses and relays: locate the starting system fuse and the starter relay; replace any blown fuses or suspected faulty relays.
- Test fuel presence and pressure: if the engine cranks but doesn’t start, you may have no fuel pressure; listen for the fuel pump prime when key is turned to ON and consider a fuel pressure test if available.
- Check for codes: connect an OBD-II scanner to read stored codes; misfires or sensor faults (like crankshaft position) can cause a no-start.
If these steps don’t reveal the issue or you encounter safety concerns, it’s wise to arrange a professional diagnosis.
When to seek professional help
Call a mechanic or roadside assistance if the Impreza won’t crank, you smell fuel around the vehicle, or warning lights indicate immobilizer or engine faults. Provide the technician with symptoms, any dashboard messages, and what you’ve already checked.
What a mechanic will likely check
To diagnose a no-start properly, a shop will typically inspect the following:
- Battery health and alternator charging
- Starter motor, solenoid, and wiring
- Ignition system and coil packs or spark plugs
- Immobilizer system, key fob, and anti-theft control
- Fuses, relays, and power supply to the starter and fuel pump
- Fuel system pressure and fuel pump operation
- Engine sensors (crankshaft/camshaft position, MAP/MAF) and ECU
- Compression and engine timing, if indicated by codes
Summary
Most Subaru Impreza starting problems stem from the battery, starter, or fuel/ignition systems, with immobilizer issues and transmission safety switches as common culprits. A structured check—starting with the battery and listening for the starter, followed by fuses, immobilizer indicators, and fuel pressure—can quickly narrow down the cause. If you’re uncertain or the car remains non-starting after basic checks, seek professional diagnosis to avoid further damage.
What happens if your car won't start but has power?
If your car has power but won't start, the problem is likely a bad starter motor, an issue with the fuel system, or a faulty ignition switch. You may hear a single click (which can point to a bad starter) or a whirring sound (which can mean a bad starter solenoid). Other less common causes include blown fuses, a security system issue, or a bad alternator.
This video explains the common issues why a car won't start but has power: 55sFixITYouTube · Jan 23, 2025
Common causes
- Starter motor: If you hear a loud click when you turn the key, the starter motor may be failing. It could be getting power, but it isn't able to turn the engine over.
- Fuel system: A bad fuel pump or clogged fuel filter can prevent the engine from getting the necessary fuel to start.
- Ignition switch: A faulty ignition switch may not be sending the "start" signal to the rest of the car, even if the lights and radio work.
- Blown fuse: A blown fuse can cause the car to have no power at all or only partial power, depending on which fuse is blown.
- Security system: Some anti-theft systems can prevent the car from starting as a security measure.
- Alternator: If your battery is getting low, the alternator may be failing and not charging the battery correctly.
What to do
- 1. Check the basics: Make sure the gear shift is firmly in Park or Neutral. Also, check that the battery terminals are clean and tight.
- 2. Listen for sounds: Turn the key to the start position and listen for any sounds. A single loud click points to the starter, a whirring sound suggests a bad starter solenoid.
- 3. Don't keep cranking: Repeatedly cranking the engine can drain the battery further.
- 4. If you suspect a specific issue, such as a blown fuse: Use a multimeter to check the fuses in the fuse box and replace any that are blown.
- 5. If you're still unsure: It's best to have the car diagnosed by a professional to avoid any further damage.
Why is my Subaru Impreza engine not starting?
One of the most common reasons a Subaru won't start is a dead or weak battery. If you hear a clicking sound when you try to start the engine or the lights on your dashboard appear dim, the issue is likely with the battery. Over time, batteries lose their charge and need to be replaced.
Why is my Subaru not starting push to start?
Try holding the key fob directly on the push button start while pressing it to start. Sometimes this can help it start. If it does, then either both key fob batteries are low, or there is a signal issue in the ignition system.
Why is my Subaru turning on but not starting?
Electrical system issues, such as blown fuses, corroded battery terminals, or damaged wiring, can also prevent a Subaru car from starting. It's essential to inspect the electrical system components and connections for signs of damage or corrosion and address any issues promptly.
