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Autopapyrus · Opel Ascona C 1.8E (18E)
https://autopapyrus.com/guides/opel/ascona/diagnosing-a-no-start-on-gasoline/
Compiled automatically from service literature and owner experience. Specs are for the typical configuration — check them against your exact car before you start.

Opel Ascona C 1.8E (18E): Diagnosing a No-Start on Gasoline

The 1.8 18E engine in the Ascona C is an 8-valve unit with Bosch multipoint fuel injection (LE-Jetronic type system) and a mechanical distributor. If the engine cranks but won't start, the cause is almost always one of three things: no fuel, no spark, or a bad air-fuel mixture. The exact procedure for this specific version is not documented in publicly available service materials, so this is the general order of checks used for fuel-injected engines of this type.

Difficulty: Medium Time: 1-3 hours Steps: 9 Tools: multimeter, test light or spark tester, fuel pressure gauge with hose, wrench and socket set, carburetor cleaner/starting fluid spray, timing light not required

Part

  • 🔩 Determined by the diagnosis. Typical candidates: fuel pump relay, electric fuel pump, fuel filter, spark plugs, spark plug wires, distributor cap and rotor, ignition module, throttle position sensor, air flow meter, fuel injectors. Prices vary widely depending on the part, so check with your supplier
There's a full repair manual for this car Every system, wiring diagrams and torque specs — not just this job. Haynes and 3 more. See manuals →

Step by step

9 steps
  1. Define the symptom. The starter cranks briskly but the engine won't catch: look for a fuel or spark problem. The starter cranks slowly or only clicks: check the battery (at least 12.4 V with the engine off, at least 9.5 V while cranking), the terminals, and the ground connections to the body and engine. If the engine catches and then stalls: suspect fuel delivery or the sensors. If the problem occurs only "on gasoline" (the car has an LPG system), first make sure the fuel selector switch is set to gasoline and that there is fuel in the tank.
  2. Check the simple things: the actual fuel level (the gauge on older cars lies), the fuses in the fuse box, and the fuel pump relay. Turn the ignition on and listen: the pump at the rear of the car should hum in the tank for 1-2 seconds. If it is silent, check for power at the pump connector and at the relay. On older cars, oxidized relay and connector contacts are a common cause.
  3. Check the fuel pressure. Connect the gauge to the fuel rail. For this type of system, the reference value is about 2.5 bar with the engine running (for the exact value, follow the manufacturer's specification). Zero or low pressure points to the pump, a clogged fuel filter, a pinched or clogged fuel line, or a faulty pressure regulator. If pressure does not hold after the ignition is switched off, the regulator, the injectors, or the pump check valve is leaking.
  4. Check for spark. Pull the wire off a spark plug and connect a spark tester (or put the plug into the wire and hold its threaded body against ground), then crank the engine. A strong blue spark means the ignition is fine. No spark on all cylinders: check the distributor cap (cracks, carbon tracking, moisture inside), the rotor, the center high-tension wire, the ignition module and coil, and the sensor in the distributor. No spark on only one cylinder: check the wire and the spark plug.
  5. Inspect the spark plugs. Wet and smelling of gasoline: the engine is flooded (from repeated cranking attempts or a leaking injector). Dry the plugs and crank the engine with the accelerator pedal fully pressed. Dry and clean: no fuel is getting in. Black and sooty: the mixture is rich. Check the coolant temperature sensor (if its resistance does not change as the engine warms up, the ECU applies the wrong enrichment) and the air flow meter.
  6. Quick fuel test: spray a little carburetor cleaner or starting fluid into the intake tract and crank the engine. If the engine fires for a couple of seconds and then dies, spark is present and the problem is fuel delivery (steps 2-3). If it does not fire at all, look at the ignition (step 4) and the mechanical side (step 8).
  7. Check the air supply and sensors: look for air leaks at the rubber bellows and hoses after the air flow meter, check that the sensor connectors (temperature, throttle position, air flow meter) are plugged in, and check the condition of the ground wires on the engine and body. On cars of this age, moisture and corrosion in connectors are often to blame after an engine wash or rain.
  8. If both fuel and spark are present, check the mechanical side: valve timing (whether the timing belt has jumped a tooth, especially if the engine cranks suspiciously easily) and cylinder compression. Normal compression for this engine in good condition is roughly 10-12 bar, with no more than 1 bar of difference between cylinders.
  9. Replace only the part confirmed by the diagnosis. After replacing the pump or filter, bleed the air out: switch the ignition on and off several times without starting the engine so the fuel rail fills with fuel.

Common mistakes and warnings

  • Work on the fuel system away from open flames, and disconnect the negative battery terminal when replacing parts. Before removing fuel hoses, relieve the pressure in the fuel rail and have rags ready. Do not crank the starter for more than 10-15 seconds at a time, because this can overheat the starter and flood the spark plugs. If you have no experience working with fuel systems and high-voltage ignition circuits, it is better to go to a repair shop.