My 2002 Volkswagen Cabrio GXL with automatic transmission experienced a sudden loss of power while driving, as if the fuel supply was abruptly cut off. After towing it home, the engine cranks normally but refuses to start. I’ve already performed several checks, and I’m feeling quite stuck. I would greatly appreciate any guidance you can offer.
Initially, I checked the ECU for error codes immediately after the incident. The only code present was P0442 – indicating a small leak in the EVAP system. After inspecting and tightening the fuel tank cap, this code has not reappeared.
Moving on to the fuel system, I discovered there’s no 12V power at the fuel pump 20A fuse terminals when the ignition key is turned to the ‘on’ position. The wiring around the fuse and relay panel appears to be in good condition. Continuity tests of the terminals to the battery positive showed normal readings, similar to other components. Suspecting a faulty fuel pump relay, I replaced it, but the car still won’t start. Is it normal for the 12V supply to the fuse terminal to be absent unless the engine is cranking? Unlike what I’ve read in forums, I don’t hear the characteristic fuel pump buzz when the ignition is switched on. However, surprisingly, when I disconnected the fuel hose at the injector rail, a strong flow of fuel was present even without the key being in the ignition or the engine cranking. (Previously, after cranking the engine with the fuel pump fuse removed, the fuel pressure was low). Furthermore, I can smell gasoline each time I crank the engine, indicating fuel delivery to some extent.
Next, I investigated the ignition system. I checked for spark at the ignition coil wire leading to the distributor and at spark plugs for cylinders 1 and 4. Sparks were present in all cases, but they seemed weak to my untrained eye (I’m unsure of what constitutes an adequate spark strength). I proceeded to replace the ignition coil and cleaned the central contact point inside the distributor, but unfortunately, the engine still refuses to start.
Finally, I inspected the timing belt, and it feels tight and appears to be intact.
Currently, I haven’t yet examined the fuel injectors or the crankshaft position sensor. I’m puzzled as to what could have caused such an abrupt engine shutdown while driving, especially since the car was running perfectly smoothly just before the problem occurred.
Any advice on further troubleshooting steps or potential causes would be immensely helpful. Thank you in advance for your expertise.
