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If your fuel injectors are putting out too much fuel, its is most likely caused by the fuel pressure regulator sine that what controls fuel pressure. Here are instructions to replace. Let me know if you have questions. Thanks
You can start out with fuel pressure test so you can know if fuel pressure is the problem or if injector pulse is the prolem. If your return line is clogged, this could also cause high pressure. Also, if you have low compression or do not have good spark, the fuel will not burn up and could cause this problem. Compression should be 131 psi minimum. If low, squirt a drop of oil in cylinder and check again. Let me know if you have more questions. Thanks
We can continue this discussion, just come back and reply to the question. Yes that is where you test the fuel pressure. If fuel pressure is too high regulator is problem. If fuel pressure is right, verify compression is good. If compression is good hte problem is the injector circuit, here is how to test. Let me know if you have questions. Thanks
Check Brown/Yellow wire from the PCM pin #12 to each of the fuel injectors is not shorted to ground. The fuel injectors are bank fired on this application so a short to ground in this wire will cause all 4 fuel injectors to open fully. 2. Remove or cut the Brown/Yellow wire at PCM pin #12 and crank the engine. If the fuel injectors are no longer held full open, the internal injector drive circuit in the PCM is shorted to ground. In this case, the PCM will need replacement. 3. If the PCM internal injector drive circuit is found faulty, be sure to verify the actual resistance of each fuel injector. 15 to 20 ohms resistance is normal. Injectors that show lower than normal resistance can stress the PCM internal injector drive circuit and cause a shorted condition.
Here is a wire diagram I pulled up. There VW diagrams are a little confusing. Let me know if you have questions. Thanks
You tested right. You can unplug the pcm and do the same tests on the pcm control side. You should not have any ground, if so, wire is bad. If no ground replace pcm. Let me know if you have questions. Thanks