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Autopapyrus · BAW BJ212 (2007), 3.2 L
https://autopapyrus.com/guides/baw/bj212/diagnosing-a-no-start-engine-cranks-but-won-t-start/
Compiled automatically from service literature and owner experience. Specs are for the typical configuration — check them against your exact car before you start.

BAW BJ212 (2007), 3.2 L: Diagnosing a No-Start — Engine Cranks but Won't Start

If the starter cranks the engine normally but the engine won't fire, the cause is almost always one of three things: no fuel, no spark, or lost timing and compression. The exact procedure for this version is not documented in publicly available service materials, so below is a general diagnostic approach, going from the simplest checks to the most involved. Check specific pressure values and clearances against the manufacturer's specifications.

Difficulty: Medium Time: 1-3 hours Steps: 11 Tools: 8-19 mm wrench set, multimeter or test light, fuel pressure gauge (if fuel-injected), spark plug socket, spark tester or a spare spark plug, compression tester, carburetor cleaner or starting fluid spray (for testing), flashlight

Part

  • 🔩 Determined by diagnosis. Typical candidates: fuel filter, fuel pump (electric or mechanical), spark plugs, high-tension (spark plug) wires, ignition coil or ignition module, distributor, crankshaft position sensor (if fuel-injected), fuel pump relay and fuses. Prices vary widely depending on the part

Step by step

11 steps
  1. Evaluate how the starter cranks. If the cranking speed is even and brisk, the battery and starter are fine. If it is sluggish, first charge or replace the battery and check the terminals and the ground connections to the body and engine. Weak cranking may not produce a spark and may not build the compression needed to start.
  2. Check the basics. Is there enough fuel (don't trust the fuel gauge alone, look into the tank)? Is the ignition switched on, and does the warning light come on? Are there any disconnected connectors or removed wires left over from recent work? Check the fuel pump and ignition fuses and relays.
  3. Check for spark. Remove one spark plug, insert it into its spark plug wire, press the threaded part against an engine ground, and crank the engine with the starter. You should see a bright blue spark. Work carefully, hold the wire only by its insulation, and keep away from fuel lines and gasoline vapor.
  4. If there is no spark: inspect the spark plugs (fouled, black, wet), the wires, the distributor cap and rotor (cracks, carbon tracking, moisture), the ignition coil, and the ignition module. Use a multimeter to check for power at the coil with the ignition on. On fuel-injected versions, also check the connector and signal of the crankshaft position sensor: if it fails, there is no spark and no injection.
  5. If there is spark, check the fuel. Turn the ignition on and listen: an electric fuel pump should hum for 1-3 seconds when the ignition is switched on. If the pump is silent, check the relay, the fuse, and the power at the pump connector. With a mechanical pump, disconnect the supply hose at the carburetor or fuel rail inlet and crank the engine: fuel should come out in distinct pulses.
  6. Check the fuel filter and fuel lines. A clogged filter, frozen water in the fuel, or a kinked hose or one that sucks in air are common causes. On a fuel-injected system, measure the pressure in the fuel rail with a gauge and compare it with the manufacturer's specification. On a carbureted engine, check the fuel level in the float bowl and make sure the engine is not flooded with gasoline.
  7. Quick test for a fuel problem: spray carburetor cleaner or starting fluid into the intake for 1-2 seconds and try to start the engine. If the engine fires and then stalls right away, there is spark but fuel is not getting through, so look for the cause in the fuel system. Use it sparingly and don't overdo it.
  8. If you have cranked the engine for a long time, the car smells of gasoline, and the spark plugs are wet, the engine is flooded. Remove the spark plugs, crank the engine for 5-10 seconds to clear the cylinders, dry or replace the plugs, then try starting with the accelerator pedal fully pressed and no choke.
  9. Check timing and mechanical condition. If the no-start appeared after work on the engine, such as removing the timing belt or chain or the distributor, check the timing marks and the distributor position. For a final assessment, measure the compression in each cylinder with a compression tester and compare the values with the specification. A sharp drop in compression points to a jumped timing chain or belt, burned valves, or worn cylinder-piston group components.
  10. Check the exhaust: a clogged catalytic converter or a badly blocked muffler can stall the engine right after it starts. If you suspect this, loosen the exhaust pipe at a joint to test.
  11. After fixing the cause, start the engine, let it warm up, and make sure the idle is stable with no dips. If the cause turned out to be the fuel filter or fuel pump, replace the filter as well as preventive maintenance.

Common mistakes and warnings

  • Work on the fuel system away from open flames and sparks, don't smoke, keep a fire extinguisher nearby, and relieve the pressure before disconnecting any lines. When checking for spark, don't touch the high-tension wires with your bare hands. If you haven't found the cause by following these steps, don't crank the starter for long periods (no more than 10-15 seconds at a time, with pauses between), and take the vehicle to a repair shop for a scan tool diagnosis and a compression test.