Alright, I'm pretty much at wit's end regarding my CEL situation...
07-14-2008, 12:49 PM
#11
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It doesn't look like i have a power output stage!
<center><img src="http://pictureposter.audiworld.com/10758/dsc_0099.jpg"></center><p>So I followed the wires, and it looks like both banks of wires lead to one main loom, which in turn heads for the ECU box. Inside the ECU box the wires look to branch out according to cylinder number (you can see the tags in the picture). I checked #4 (the cylinder with the problematic cold-start misfires), and all wires seemed to be in excellent condition, no corrosion, and connected tightly. Am I not looking in the right place for the output stages? What else do you guys think I should try?
07-14-2008, 01:19 PM
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Somewhere near the evap valve on my old bus-you will hae them
They are what distributes the order to fire to the individual plug- your issue in the well above post may well be the vacum leak but Im pretty sure the missfire will be the output stage
07-14-2008, 02:25 PM
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Thanks for confirming I'm not crazy! So back to the problem at hand, I need to firstly
remedy the evap issue so I can take it to get emissions tested. I guess I'll start with the testing of the purge valve, and maybe replace the tubing that connects it (it's looking old and crackly as it is). Does this sound like a good first step? Also, where would the best place to get a replacement valve be?
07-14-2008, 05:00 PM
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So FWIW, the actual Bentley website is actually pretty helpful.
It seems that my evap issue is most likely due to a bad purge valve (which I'll test tomorrow). The rough idle could be due to either a stuck injector, or a bad fuel pump. This will have to be investigated more. Sure wish I had a Bentley manual right about now...*sigh*.
07-17-2008, 08:41 AM
#20
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Getting any other funky ECU codes?
If so, it could be your ECU is wet.
Do you have an oil leak into the plug well from the cam cover gasket? this could cause misfire issues. Try using a dab or three of dielectric grease on the coil boot so it seals to the plug body.
You moved the coils and the plugs but the misfire still stays with 4? Can you get a misfire from a fueling issue? If you squeeze the return line on the fuel pressure regulator when the problem occurs does it help? If so, maybe regulator or fuel pump?
Is the wiring plug to the #4 coil clean and free of corrosion?
Do you have an oil leak into the plug well from the cam cover gasket? this could cause misfire issues. Try using a dab or three of dielectric grease on the coil boot so it seals to the plug body.
You moved the coils and the plugs but the misfire still stays with 4? Can you get a misfire from a fueling issue? If you squeeze the return line on the fuel pressure regulator when the problem occurs does it help? If so, maybe regulator or fuel pump?
Is the wiring plug to the #4 coil clean and free of corrosion?
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