AU 1 ,I6 , not sparking on Number 1

efirestorer · 13-03-2011, 10:04 AM

While attempting to cure slight hesitation when cold , tightened manifold screws ( 90% of them loose ) and in process unwittingly dislodged lead from coil pack to Number 1 . Wife then drove 5 K with misfiring engine. On checking I located the loose lead , replaced it. NO JOY . Tried a new lead , still no spark. Only on number 1. Is there a diagnostic code recorded by the computer , and how do you access it ,to show faulty coil pack ? I have read another post on replacing the coil pack and will do so , but I am checking to see if any shortcut via code and whether any other problems are indicated. Any suggestions in Melbourne for point of supply for new coil pack apart from Ford.

GOLDIE · 13-03-2011, 10:21 AM

it will be the coil pack

ian

FGII-XR6 · 13-03-2011, 11:52 AM

I would replace the lead, if the coil pack was faulty you would be down 2 cylinders as the AU coil pack uses a "wasted spark" system, one coil firing 2 cylinders at the same time so barring physical damage to the coil terminal the coil pack is unlikely to be faulty on only 1 cylinder
If you don't understand wasted spark check this out http://www.crypton.co.za/Tto%20know/...sted%20sp.html

efirestorer · 13-03-2011, 12:17 PM

Thank you au3xr6 , I have already tried a new lead on number 1 , and all others appear to be firing , which cylinder in AU would be firing at the same time as number 1 ? so that I can doubly check spark on that one.

FGII-XR6 · 13-03-2011, 12:30 PM

1 and 6 are on opposing cycles so they would share the same coil the same applies to 2 and 5, and 3 and 4

AMB · 13-03-2011, 08:08 PM

In wasted spark the current goes in one lead to the plug, then out the other plug and back to coil. So when one of the leads is unplugged accidently, the spark can't return, so I wonder if that is enough to damage the coil?

Beer Baron · 13-03-2011, 10:50 PM

Quote:

Originally Posted by AMB

In wasted spark the current goes in one lead to the plug, then out the other plug and back to coil. So when one of the leads is unplugged accidently, the spark can't return, so I wonder if that is enough to damage the coil?

It can damage the coil but like au3xr6 said it would take out number 1 and 6. If its 2 cylinders down its going to be a violent shake.

Are you checking spark at the lead or the spark plug ?

FGII-XR6 · 13-03-2011, 11:26 PM

no the HT is induced in the coil and fed to both leads similar to a centre tap transformer supplying 2 different circuits. the HT in both leads goes through the plug to earth not to the other plug

Quote:

Originally Posted by AMB

In wasted spark the current goes in one lead to the plug, then out the other plug and back to coil. So when one of the leads is unplugged accidently, the spark can't return, so I wonder if that is enough to damage the coil?

AMB · 13-03-2011, 11:30 PM

Quote:

Originally Posted by Beer Baron

It can damage the coil but like au3xr6 said it would take out number 1 and 6. If its 2 cylinders down its going to be a violent shake.

Are you checking spark at the lead or the spark plug ?

Right, so he may have damaged the coil, but like you said, if it is buggered then both plugs won't be firing. But efirestorer, you are saying only 1 plug is not sparking, so have you pulled the plug and checked for cracks etc , or replaced it?

efirestorer · 14-03-2011, 08:02 AM

Thanks all , I have been checking for spark by holding plug end connection against earth ( the block) and Number 6 IS FIRING , but with new lead on 1 , still no spark BUT I now notice slight spark type noise when engine switches off. Could it be that I have damaged coil pack terminal for number 1 ? Coil pack will have to come out to do a proper visual check on terminal 1!?

FGII-XR6 · 14-03-2011, 11:19 AM

Quote:

Originally Posted by efirestorer

Could it be that I have damaged coil pack terminal for number 1 ? Coil pack will have to come out to do a proper visual check on terminal 1!?

good chance thats the problem

efirestorer · 18-03-2011, 11:14 AM

Thanks again for all advice. Problem solved with new coil pack. Visual inspection revealed that number 1 had been arcing for a long time , possibly since the installation of new ignition leads by the Ford Dealer. I had dislodged it completely without any undue force , and arcing may have continued internally to lose spark completely for number 1 and not affect number 6.