confused!!

[thebeach2008]

hi I have a query
my engine code is DG 099117*
the van has WR7CC plugs in get Haynes states van with green sticker coil should be W7DTC ,according to Haynes the plugs I have in are for low compression 2ltr engine, another company on ebay say that WR7LTC+2 will fit yet they show up for a 1.6 diesel and just kampers are saying WR7DC, does anyone have any idea what the correct plugs should be, im guessing the star stamped next to the engine number is that is a recon as it was changed in 2009, any help would be great many thanks gary

[edoh]

av u ad a look at -
https://club8090.co.uk/wiki/Pe ... plug_types" onclick="window.open(this.href);return false;

[thebeach2008]

hi thanks for that , yes I had read that and that just add more confusion as im looking for bosh but cant find those ones anywhere

[bigherb]

W7DTC which are a long life plug.

http://www.gsparkplug.com/shop/bosch-w7dtc.html" onclick="window.open(this.href);return false;

[thebeach2008]

thanks for that I have gone for those thanks for all your help cheers

[California Dreamin]

VW Started out using good old (Bosch) single electrode W7D then copper cores came out so they went to W7DC....still single electrode.
Then despite the fact that the wasserboxer HT leads are already heavily surpressed (so they don't interfere with tellies and radios's) with resistors in the rotor arm, lead ends and plug caps someome felt it was necessary to also include a resistor in the spark plugs as well so they they turned to WR7DC again still one electrode.
Then to compete with other manufacturers in the 'trend' towards longer service intervals and minimal servicing down time and costs, Bosch brought out the triple electrode W7DTC and then the Supa 4 (same as three but with 4 lol.)

That was just Bosch....NGK & BERU also followed a similar path....then there is platinum tipped irridium, V groove etc etc.

If I were recommending a replacement it would probably be straight reliable W7DC (non surpressed copper core).
The trouble with the multi electrode types is their air gaps are non adjustable at about 0.9mm and the specification shows the gap needs to be 0.7mm.

You can still get W7DC plugs and they are fairly reasonably priced.

http://www.ebay.co.uk/itm/4x-Bosch-Supe ... 966wt_1199" onclick="window.open(this.href);return false;

Martin

[AdrianC]

another company on ebay say that WR7LTC+2 will fit yet they show up for a 1.6 diesel

It's safe to say that anybody saying _any_ spark plug should be used in _any_ diesel can be thoroughly ignored...

Bosch spark plug codes :-
http://www.gsparkplug.com/shop/media/im ... _bosch.pdf" onclick="window.open(this.href);return false;

(and all other major manufacturers)
http://www.gsparkplug.com/shop/spark-pl ... rers-code/" onclick="window.open(this.href);return false;

So...
Reformat 'em so you can see at a glance what characters line up with what...

Code: Select all

W.R.7.C. .C
W. .7.D.T.C
W.R.7.L.T.C.+2
W.R.7.D. .C

All are the same thread - W (M14 x 1.25)
Three of the four have resistors for ignition suppression - R
All are the same heat range - 7
All plugs are the same length, but one has 1mm of plug nose beyond the base, two have 3mm, one has 5mm - C/D/L
Two have triple electrodes - T
All have copper electrodes - C
One has "binary" ground electrodes - +2

Basically, they'll probably all be as good as each other, some'll be cheaper, some are "fancier". I'd always go with a resistor plug.

[thebeach2008]

thank you both for the replies I have learnt a lot cheers gary

[ghost123uk]

another company on ebay say that WR7LTC+2 will fit yet they show up for a 1.6 diesel

I wonder what water pump they recommend for the early air cooled version of our vans

Seriously though, I would go with Martins recommendation =

If I were recommending a replacement it would probably be straight reliable W7DC (non surpressed copper core).

[California Dreamin]

Bosch WR7DC seem to be the most commonly available (listed) spark plug, but as I said...I prefer them without the added suppressor so:(W7DC) because there is already plenty of resistance added all the way back to the coil (the rotor arm/plug lead ends & spark plug caps all have built in 'added' suppression) I have never experienced any sort of radio or television interference using them.


The benefit from using these single electrode plugs is that they can be adjusted to the specified 0.7mm gap 'unlike the triple & quadruple types' the only difference being that they need changing every 12,000 miles. However, If you are like me and don't do a massive amount of miles, that's new spark plugs every two years (re-gaping every year). No biggie!

Martin