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Discussion Starter · #1 · (Edited)
I am having really big trouble with my car and if I can't fix it within the next 48 hours then I am going to get rid of it because I don't have time it anymore.

I hosed down my engine bay and now I get a battery warning light. This is what I have done so far to try and fix the problem:

  • Checked and replaced ACG(S) fuse (37) and alternator/fuel pump fuse (12)
  • Fully charged my battery
  • Replaced the alternator with a remanufactured unit
  • Replaced the crankshaft pulley


The crankshaft pulley was bad. The outer pulley which drives the alternator had separated from the inner pulley. I thought for sure this was the problem. Replacing it did nothing!

I haven't checked the wiring with a multimeter as I don't have one but if it is the wiring then that is a big job to fix which I don't have time for.

I haven't change the alternator belt but I tightened the belt hard which didn't help so I don't think the belt is the problem.

The ECU doesn't report any problems.

The only thing left that I can think of that is causing the problem is the wiring. :(

I am out of ideas and going into denial as I hope to hold onto my car for a bit longer. If anyone knows something - anything! please let me know. I need a miracle!
 

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Test the alternator and the battery with a multimeter. There's several videos on youtube on how to do this. Check for things like the power output from the alternator while it's running, the power going to the battery, and so on. You should be able to narrow it down to either a problem with the alternator, the battery, or some resistance/breakage in the wiring.
 

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Discussion Starter · #3 ·
The alternator and battery are fine. There is not point checking the wiring because I won't be fixing the wiring. I am already thinking it's the wiring. What else could it be... :/

I am hoping the problem is something outside the box that is being overlooked. I am having a hard time accepting that water could affect the wiring like this. The water is long gone.

I see there is a main battery fuse. It is fine also. If that fuse blew then I am guessing no power would get to the car and it would be the equivalent of disconnecting the battery. Does that sound right?
 

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How long has it been since you wet the engine? hours, days?
 

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Discussion Starter · #5 · (Edited)
I hosed it down two months ago. I covered the battery, fusebox, and distributor when I did it and didn't turn on the car until two days later which is when the battery warning light came on. After I changed the alternator I fully charged the battery with a charger. When I started the car the battery warning light didn't come on but then half an hour later it did come on and soon after the battery went flat.

I fully charged the battery yesterday while I was changing the crankshaft pulley. This time the battery charge light came on straight away.

The problem must be the engine wire harness! Right?!
 

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Discussion Starter · #6 · (Edited)
You know, there is one difference between this time round and last time. Last time I did a couple of rounds on the engine wire harness alternator connector with WD-40 as it was clogged with gunk. I now realised I didn't think anymore of it because I thought the battery charge light didn't come on straight away because I had a fully charged battery, but it didn't happen this time round so there goes that theory which leaves the only thing different this time round which was not cleaning the connector. Tomorrow I am going to get out my pick set and pull apart the connector and clean it hard with vinegar! That is all I have on hand.
 

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Discussion Starter · #8 · (Edited)
I like your optimism mate, but I have gone over the entire circuit diagram for the alternator throughout the entire car. I have checked or replace everything except the belt and engine wire harness. What else could it be?


I just checked out the alternator connector that I sprayed into twice a couple of months ago with WD-40 to clean it up. There is still a lot of gunk in there and residual WD-40 as well. I want to take out the terminals so I took off the back part of the connector with a pick, but I can't figure out how to get the terminals out. There seems to be an inner and outer section of the connector. Does anyone know what the trick is?

29200


29201



This was sunrise here in Melbourne this morning while working on the car. Just feel like being random. :)

29203
 

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I just checked out the alternator connector that I sprayed into twice a couple of months ago with WD-40 to clean it up. There is still a lot of gunk in there and residual WD-40 as well.
Yeah you're not supposed to do that. If you put grease or oil in the places where the metal terminals connect, it will create resistance and cause a bad connection. Spray both ends with electric parts cleaner, plug it back in, test the connection with a multimeter, then start it.
 

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  • Engine misfires
  • Rough idle
  • A decrease in car power, especially in acceleration
  • Poor fuel economy
  • Difficulty starting the engine
  • Check engine light is on
  • Exhaust backfiring
  • Increased hydrocarbon emissions
  • The smell of gas coming from the exhaust
  • Fuel leaks
 

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  • Engine misfires
  • Rough idle
  • A decrease in car power, especially in acceleration
  • Poor fuel economy
  • Difficulty starting the engine
  • Check engine light is on
  • Exhaust backfiring
  • Increased hydrocarbon emissions
  • The smell of gas coming from the exhaust
  • Fuel leaks
How many symptoms you have from this list?
 

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Discussion Starter · #14 · (Edited)
Stub

WD-40 is apparently non-conductive so it shouldn't be interfering with the circuits. Still, the connector was flooded with WD-40 and it didn't look right. WD-40 isn't even a contact cleaner agent. It's sticky so it can't be good at cleaning out oxidised gunk. If it was a contact cleaner then the WD-40 contact cleaner variant wouldn't exist. I noobed it.

I now think this ordeal started by water getting into the socket and interfering with the circuits after I hosed down the engine. I can't figure out why the problem persists but as I said, the WD-40 filled connector doesn't look right. The claim that WD-40 isn't conductive seems to be an internet myth. I can't find any statement from the company behind WD-40 stating that it's non-conductive.

Today I drenched the connector with vinegar and let it sit for 10 hours. Vinegar is a mild acid and is the only contact cleaning agent I have on hand. Afterwards I drenched the connector with water to wash away the vinegar and broken down gunk. I am going to let it dry overnight and then see if it fixes the problem tomorrow. If it doesn't fix the problem then it can only mean the engine wire harness is gone in which case I will get the car towed for scrap and call it a day.


DON NADIE

I don't have any of those symptoms.
 

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Stub

WD-40 is apparently non-conductive so it shouldn't be interfering with the circuits. Still, the connector was flooded with WD-40 and it didn't look right. WD-40 isn't even a contact cleaner agent. It's sticky so it can't be good at cleaning out oxidised gunk. If it was a contact cleaner then the WD-40 contact cleaner variant wouldn't exist. I noobed it.

I now think this ordeal started by water getting into the socket and interfering with the circuits after I hosed down the engine. I can't figure out why the problem persists but as I said, the WD-40 filled connector doesn't look right. The claim that WD-40 isn't conductive seems to be an internet myth. I can't find any statement from the company behind WD-40 stating that it's non-conductive.

Today I drenched the connector with vinegar and let it sit for 10 hours. Vinegar is a mild acid and is the only contact cleaning agent I have on hand. Afterwards I drenched the connector with water to wash away the vinegar and broken down gunk. I am going to let it dry overnight and then see if it fixes the problem tomorrow. If it doesn't fix the problem then it can only mean the engine wire harness is gone in which case I will get the car towed for scrap and call it a day.


DON NADIE

I don't have any of those symptoms.
This means you wiring is good.
 

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Discussion Starter · #19 ·
Thanks for the heads up about the silicon spray.

I like hearing you say the wiring is good but could you please tell me why you think the wiring is good? :)
 

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This is just a never ending cycle of you asking for advice, getting advice, deciding the advice is wrong, fucking things up ever more, asking for advice.
 
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