Strange backfire

Hi guys had a spare couple of hours today so decided to change pollen filters and plugs and leads.
Well I wish I never bothered,as I now have a strange backfire which sounds like its coming from the right bank as you look at engine from the grill, it seems to be back firing round the cat area.
So I changed everything back put old plugs in and leads back on its still there.so tbh I'm pretty p****d off at the minute.
Any help guys please? Only thing I can think is if plugs not tightened all the way in or if plug lead round the wrong way, so would anyone have a picture please of plug to coil set up please?
All help appreciated

I would double check the firing order of the HT leads first.

http://discoii.files.wordpress.com/2011/10/dii-firing-order.jpg

This is for the disco v8 which I think is the same for the Thor V8

Is your engine a GEMS or THOR?

im thinking you have your leads on wrong you got 2 mixed up some where

I don't know if it's a gems or a Thor how can I tell?
It says 4.0 on the top

pimpedrange said:

I don't know if it's a gems or a Thor how can I tell?
It says 4.0 on the top

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This is what a Thor engine looks like:

Range Rover P38 4.6 Thor Engine Good Runner 44000 Miles *All Parts Available* | eBay

This is what a GEMS engine looks like:

http://www.ebay.co.uk/itm/like/1913...1=ICEP3.0.0-L&ff12=67&ff13=80&ff14=108&ff19=0

http://www.rangerovers.net/forum/7-range-rover-mark-ii-p38/41107-ht-lead-sequence-diagram.html for GEMS

Mines a gens then,

Sorry I meant gems

Hi guys,the link to the discovery shows 2 separate coils, my car has just the 1 coil pack fitted?

All sorted guys thanks got 2 plugs for right bank wrong way round, I blame the lack of concentration from when the kids come out and disturbed me

pimpedrange said:

All sorted guys thanks got 2 plugs for right bank wrong way round, I blame the lack of concentration from when the kids come out and disturbed me

Click to expand...

Must add that to the "Book of Excuses"