Fuel System:
* Fuel Pump: The most likely culprit. The fuel pump might be failing, weak, or not getting power. You'll need to check:
* Power at the pump: With the ignition on (but not cranking), check for power at the pump's wiring connector. If no power, trace the wiring back to the fuel pump relay and/or the fuse.
* Fuel pressure: You'll need a fuel pressure gauge to check pressure at the fuel rail. This confirms if the pump is delivering adequate pressure. The pressure should be within the specifications listed in your owner's manual or a repair manual. Low pressure or no pressure points directly to the fuel pump.
* Fuel pump relay: Replace the fuel pump relay – they are inexpensive and a common point of failure.
* Clogged Fuel Injectors: While less likely immediately after a filter change, severely clogged injectors could still restrict fuel flow. A fuel injector cleaner might help, but a professional cleaning or replacement may be necessary.
* Bad Fuel: Old, contaminated, or water in the fuel tank could still be causing issues even with a new filter. Consider draining some fuel from the tank to check its quality.
Ignition System:
* Spark: Check for spark at the spark plugs. A weak or absent spark means problems with the distributor cap, rotor, ignition coil, ignition module, or even the wiring.
* Ignition Coil: A failing ignition coil can cause intermittent or no spark.
* Distributor Cap and Rotor: These wear out and can cause misfires or prevent starting. Inspect them for cracks, corrosion, or wear.
* Spark Plugs and Wires: Check the condition of your spark plugs and wires. They might be fouled, worn, or damaged.
Other Possibilities:
* Battery: A weak battery can prevent starting, especially in older vehicles. Test the battery voltage.
* Starter Motor: A faulty starter motor won't crank the engine. Listen for the starter's engagement sound when you turn the key.
* Security System (if equipped): If your Suburban has a factory or aftermarket security system, it might be preventing the engine from starting.
* Computer/ECU Issues: Less likely but possible, a problem with the engine control unit (ECU) could be causing the no-start condition.
Troubleshooting Steps:
1. Check the obvious: Battery voltage, fuel in the tank (more than just a tiny bit).
2. Test for fuel pump power and pressure. This is the most likely culprit.
3. Check for spark at the spark plugs.
4. Inspect the distributor cap, rotor, spark plugs, and wires.
5. Replace the fuel pump relay (it's cheap and easy).
If you're not comfortable working on your vehicle's electrical and fuel systems, it's best to take it to a qualified mechanic. Attempting these repairs without the proper knowledge and safety precautions could lead to injury or further damage. Remember to always disconnect the negative battery terminal before starting any electrical work.
