Leads - is this right.

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mhj
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Leads - is this right.

Postby mhj » Sat Oct 27, 2018 1:23 pm

So rats chewed the leads and it was running roughly . I changed the leads but foolishly failed to take note of the order. I think I figured it out but would appreciate confirmation... because the bloody thing isn’t starting now
.
I wonder if it’s the coils ?

Any suggestions appreciated

Enjoy
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Re: Leads - is this right.

Postby RS2000 » Sat Oct 27, 2018 1:51 pm

No, it won't start like that.
Starting with the drivers side coil (lowest in photo), it's 4, 1, 2, 3.
The no's are stamped on the rear side of the coil bracket, but you need a mirror to see them.

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bruce
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Re: Leads - is this right.

Postby bruce » Sat Oct 27, 2018 1:52 pm

Goggle up some engine bay pics - I think there is a slight difference in your order at the back.
I'd recommend the blue wax blocks to kill rats. I had a biggie and he ate two blocks before expiring.

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Re: Leads - is this right.

Postby 93_Clubman » Sat Oct 27, 2018 2:20 pm

Hey Martin, just had a look in the NA8 workshop manual (as my 1993 NA8 runs CoP) & firing order is 1342 with number cylinder being the closest to the radiator. IIRC, should be the same on the NB8A as coils were only slightly different, ie 3 pin instead 4 pin connector.

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Re: Leads - is this right.

Postby RS2000 » Sat Oct 27, 2018 2:31 pm

Yes, the firing order is 1,3,4,2, but the coil order is 4,1,2,3 drivers side to passenger side

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Re: Leads - is this right.

Postby 93_Clubman » Sat Oct 27, 2018 2:34 pm

Same manual but on the coils page says: Viewed from the rear (see photo) the coil towers - left to right - connect to sparkplugs as follows: 3214. So 3 is exhaust side while 4 is intake side.

mhj
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Re: Leads - is this right.

Postby mhj » Sat Oct 27, 2018 4:04 pm

thanks for the replies
did the 4123 thing.. turns over better !??!. but still hasn't started.. I will give it another charge and a little rest .. for both the car and myself . then give it another go. I hope I haven't cooked the coils or something.??? very frustrating
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Re: Leads - is this right.

Postby hks_kansei » Sat Oct 27, 2018 6:25 pm

The stock system only has 2 coils, but each one has 2 leads from it.

One coil does 1+4 the other 2+3

If what you've got doesnt work, just swap the 2 left leads with the 2 right ones.


Doesnt matter if the coil has the leads plugged in as 1-4 or 4-1, since it fires both plugs at the same time it wont make any difference.



If it's an NB8A then the left side coil (near the intake manifold) will be the 1/4 coil.
1999 Mazda MX5 - 1989 Honda CT110 (for sale) - 1994 Mazda 626 wagon (GF's)

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hks_kansei
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Re: Leads - is this right.

Postby hks_kansei » Sat Oct 27, 2018 6:31 pm

mhj wrote:I hope I haven't cooked the coils or something.??? very frustrating


they'll be fine from having the leads on wrong.
Only real way to cook a coil (other than age etc) is to leave the car on ign for ages, since they can charge up and cook themselves without discharging.

But yeah, with leads on wrong they'll just be sparking on the wrong cylinder, worst case it fires and blows the intake pipe apart with a backfire.


Just curious, have you changed the plugs at all?
usually that's the first port of call, especially if you've been cranking it with the leads on wrong, there's a good chance it's flooded and fouled the plugs (no spark on compression = fuel doesnt burn = next cycle more fuel = still no burn = plugs get soaked and wont spark)

If the plugs are new then just pull them out and give them a wipe off, if they've been in for a while then may as well spend the $16 to put new ones in.
1999 Mazda MX5 - 1989 Honda CT110 (for sale) - 1994 Mazda 626 wagon (GF's)

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Re: Leads - is this right.

Postby 93_Clubman » Sun Oct 28, 2018 12:33 pm

Assuming this is on your SC'd NB8A, what engine management are you running?

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Re: Leads - is this right.

Postby bruce » Sun Oct 28, 2018 2:36 pm

I reckon Mr Rat has chewed some other wiring as well?

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Re: Leads - is this right.

Postby mhj » Sun Oct 28, 2018 4:33 pm

its got an adaptronic ecu.. and maybe more was bitten.. or maybe the coils died independently to rat deprivation.
atm I'm thinking Nrma road service membership . wait three days then towed to auto electrician
I live in a small town about half an hour from a town with an auto electrician.
the joys of car ownership.. though to be fair when I used it daily rather than occasionally it never missed a beat
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Re: Leads - is this right.

Postby project.r.racing » Sun Oct 28, 2018 5:59 pm

getting spark?

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Re: Leads - is this right.

Postby 93_Clubman » Mon Oct 29, 2018 11:17 am

^+1
Btw, if it's coil related, which is a common weakness on the NB8A, then it's usually one of the two coils in the pack pair that goes. Other common NB8A weakness was the wiring loom leading to the coilpack - wires are bent & unsupported & often the wires weaken & break. Black_Penguin has/had an NB8A & is/was not far from you - perhaps he has a stuffed coilpack that you could try one of the coils out of with one of yours: memberlist.php?mode=viewprofile&u=7391

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hks_kansei
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Re: Leads - is this right.

Postby hks_kansei » Mon Oct 29, 2018 12:38 pm

mhj wrote:its got an adaptronic ecu.. and maybe more was bitten.. or maybe the coils died independently to rat deprivation.
atm I'm thinking Nrma road service membership . wait three days then towed to auto electrician
I live in a small town about half an hour from a town with an auto electrician.
the joys of car ownership.. though to be fair when I used it daily rather than occasionally it never missed a beat



Pretty sure the Adaptronic (well, the later Select standalone anyway) has testing features in WARI/Eugene

You should be able to plug in the laptop with the leads removed and fire each coil manually to confirm spark.
Or just do the old fashioned way of having someone crank the engine while you check the plugs on the rocker cover.




My money is still on it having flooded when the leads were on wrong.
Pull the spark plugs and look at them. Then replace them.
1999 Mazda MX5 - 1989 Honda CT110 (for sale) - 1994 Mazda 626 wagon (GF's)


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