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Q: INTERMITTANT STARTING

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MY CAR RUNS GREAT FOR AWHILE THEN ON OCCASION IT TAKES A DAY OR TWO BEFORE IT WILL START AGAIN. REPLACED FUEL PUMP RELAY RECENTLY.

Your engine needs a few things to start and run: Compression, Fuel, Spark, Timing, and Voltage.

An intermittent no-start would lead me towards no spark or no fuel pressure. You need a fuel pressure gauge to check the fuel pressure when it does not start. You should see at least 35 PSI or more when starting. If the pressure drops after sitting or is lower than 35 PSI, then you likely need a fuel pump replacement. Fuel pump problems are common on this vehicle.

After verifying fuel pressure, checking the spark requires a spark tester to ensure that a spark is reaching the cylinders. This test is a little more difficult as removing the wires from the spark plugs on an older vehicle may cause them to break. Depending on the age of the ignition components (ignition coil, distributor cap, rotor, wires, plugs), they may need to be replaced.

Intermittent conditions are hard to find and require diagnosis when a problem occurs. There may be anything from an electrical issue to something basic as listed above. I listed the two common issues above. If you still need assistance, you should talk to a qualified mechanic. A certified mobile mechanic from YourMechanic can inspect your vehicle’s starting issues at your home or office.

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