78 GLS misfire

[wyke]

My daily 78 GLS started to kangaroo a bit last week.
I did a poits cap and rotor renewal as they looked a bit worn ( 34k car )

However - now no spark at num 2 lead. Checked plug and lead.
ticks over lumpy and revs but no power and it is just num 2 !!!
rest points and static timing.
Please help , I had to have a lift to work today - can`t have vivas getting a bad name

[northern nutter]

Its process of elimination if 1,3 & 4 are ok try swopping number 2 plug and lead with number 3
if the fault moves to number 3 its the lead or plug.
If the fault is still at number 2 then try the disy cap.
Hope this helps.
 
Deon

This post was made via email to the Vauxhall Viva Owners Club
Visit us at www.vauxhallviva.com

[Sid]

Could be spark leaking to earth via faulty lead insulation or tracking in
the distributor cap. Only way to be sure is replace cap lead and plug with
known good items preferably new in the case of the plug and distributor cap.

Sid

----- Original Message -----
From: "wyke" <grahammc@blueyonder.co.uk>
To: <mechanicalhelp@vauxhallviva.com>
Sent: Monday, January 16, 2006 11:23 PM
Subject: 78 GLS misfire


>
> My daily 78 GLS started to kangaroo a bit last week.
> I did a poits cap and rotor renewal as they looked a bit worn ( 34k car )
>
> However - now no spark at num 2 lead. Checked plug and lead.
> ticks over lumpy and revs but no power and it is just num 2 !!!
> rest points and static timing.
> Please help , I had to have a lift to work today - can`t have vivas
getting a bad name
> _________________________________________________________
> This email was sent from the vauxhall viva owners club forum
> Visit us at www.vauxhallviva.com
>



This post was made via email to the Vauxhall Viva Owners Club
Visit us at www.vauxhallviva.com

[wyke]

Thanks for help - I have tried most of these.
Replaced cap and rotor and changed leads around and no spark across air gap when I remove 2 lead from dizzy ( which is what the other leads do ).

Does widening points gap help ?

Could it be plar on shaft - for a 34k car , it would seem strange.?

[Sid]

No, widening the points gap would make it worse if anything as the coil has less time to charge, however your method of testing for
a spark isn't conclusive. Even the plug gap being a bit too big or the plug resistance being too high (e.g. faulty plug) could be
enough to prevent that test working, though clearly there's *something* causing the spark to be weaker on that cylinder.
Swapping the plug and lead with one from another cylinder to see if the fault migrates is worth a try. If it stays on the same
cylinder then its certainly a cap fault. If it moves then it's the plug or lead. Swap back just the lead, leaving the plugs swapped,
and you'll narrow it further depending on the result.

If the fault stays on the same cylinder after swapping everything it could be that your head gasket is letting water get into the
cylinder. I've had this problem many times I'm sad to say.

Ignition faults *can* be hard to trace though. I've frequently had to replace plugs, points, cap, leads and rotor, and even the
coil, all at the same time to cure misfires, but when I've failed its been the head gasket.

Sid

----- Original Message -----
From: "wyke" <grahammc@blueyonder.co.uk>
To: <mechanicalhelp@vauxhallviva.com>
Sent: Tuesday, January 17, 2006 10:05 PM
Subject: 78 GLS misfire


>
> Thanks for help - I have tried most of these.
> Replaced cap and rotor and changed leads around and no spark across air gap when I remove 2 lead from dizzy ( which is what the
> other leads do ).
>
> Does widening points gap help ?
>
> Could it be plar on shaft - for a 34k car , it would seem strange.?
> _________________________________________________________
> This email was sent from the vauxhall viva owners club forum
> Visit us at www.vauxhallviva.com



This post was made via email to the Vauxhall Viva Owners Club
Visit us at www.vauxhallviva.com

[Sid]

> If it stays on the same cylinder then its certainly a cap fault.

Ooops, I meant to say "probably" not "certainly" as of course there are other possible non-electrical causes as I mentioned
afterwards.

Sid