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Weird electrical problems! Need help

Jimoffy1

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So I decided to service my car. Spark plugs changed, gapped to 1.5mm. Brand new ngk spark plugs, and new ngk coil pack. I have tested everything, coils work, spark plugs spark, and leads spark. Car was fine before I changed everything. Now I have all the cables in the right place, car barely starts, backfires a little and it’s very very rough. Undriveable.

While my friend was cranking the car earlier tonight I saw a glowing from passengers side of engine under header near spark plug hole. When you crank the car it seems like there’s a voltage leak. I have a video I’ll post a link.

I have tightened the spark plugs in properly, pushed the leads on as hard as I can. I even put the old leads and spark plugs back in # 1,3, and 5, which where working, it’s still doing it: what the hell did I do wrong?

https://www.dropbox.com/s/422bm9jv0jqdulh/Video 12-8-20, 7 50 50 pm.mov?dl=0
 

krusing

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That looks like the Starter Motor is arcing, I would be replacing that, because if you a fuel leak, You will get a Bang For Ya Buck !
1.5 gap is to big, it should be 1mm,
Make sure you have the correct lead on the correct coil, as its easy to mix them up.
I would put the old coils back in, and see if it fires up,
Why did you replace them ? was there an issue before ?
 
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Jimoffy1

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That looks like the Starter Motor is arcing, I would be replacing that, because if you a fuel leak, You will get a Bang For Ya Buck !
1.5 gap is to big, it should be 1mm,
Make sure you have the correct lead on the correct coil, as its easy to mix then up.
I would put the old coils back in, and see if it fires up,
Why did you replace them ? was there an issue before ?
My spark plugs that I pulled out originally that where working where gapped to almost 1.8mm. I have read that for the 3.8 1.5mm is fine. Maybe I will try 1mm thoigh. Leads are in right places, I only replaced them because I was bored and car hit 200000km. Regretting it now!!
 

krusing

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My spark plugs that I pulled out originally that where working where gaped to almost 1.8mm. I have read that for the 3.8 1.5mm is fine. Maybe I will try 1mm thoigh. Leads are in right places, I only replaced them because I was bored and car hit 200000km. Regretting it now!!

The Resistance of the Leads should be approx 900ohms [+/- 100ohms]
If they are with in that range, they should be ok, unless they are cooked or damaged internally
As a matter of cause, I did mine on my L67 a few weeks ago, and instead of running them a single black plastic split conduit,
[for the drivers side]
I ran the 3 of them in a separate 12mm split conduits, so they don't/cant cross arc between them.
Also, did you use OEM or Aftermarket Leads ?
 

Skylarking

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No need for two threads about the same problem, maybe the moderators can merge this thread with this one..

haha, typed this and, oddly, pressed post which didn’t work, so now there are 2 more replies before pressing posting again to insert comment :p
 
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Jimoffy1

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The Resistance of the Leads should be approx 900ohms [+/- 100ohms]
If they are with in that range, they should be ok, unless they are cooked or damaged internally
As a matter of cause, I did mine on my L67 a few weeks ago, and instead of running them a single black plastic split conduit,
[for the drivers side]
I ran the 3 of them in a separate 12mm split conduits, so they don't/cant cross arc between them.
Also, did you use OEM or Aftermarket Leads ?
I will measure them tomorrow. The leads are crossed, they where originally anyway. Same leads and spark plugs I bought that where already in the car. Ngk..
 

mechanic

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Backfiring is a symptom of incorrect firing order.
Check your lead placement. Ensure the cylinder you think is no. 1 is actually no. 1.
 

krusing

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I will measure them tomorrow. The leads are crossed, they where originally anyway. Same leads and spark plugs I bought that where already in the car. Ngk..

Here is a image of what sequence the Coil Parks should be installed, that I borrowed from the Web,
which also indicates what cylinder number they are.
Also an extract of the pages for the Ignition System that also indicated the Coil Positions.
NB: It also states 1.5mm plug gap, but IMHO, it is too wide, with my past experiences, engines seem to idle better with a 1mm gap,
and wont cause them spark across other/older Spark Plug Leads that can leak.
 

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Skylarking

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Here is a SnapOn Holden Engine Troubleshooting Manual that is helpful when one has electrical problems. In my quick scan of the doc, it doesn’t show cylinder & DFI numbering but it’s worthy reference to have...

WikI does state the following for the L36

This engine has the cylinders numbered 1-3-5 on the left-hand bank (front bank for FWD applications) and 2-4-6 on the right-hand bank, the number 1 cylinder being the furthest from the flywheel end. The firing order is 1-6-5-4-3-2.
Also, even though it’s for a FWD engine, the following g video may be helpful:


Did you have a good look at #3 spark plug hole and also check the alternator yet?
 
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