hello
looking for spark plugs for the 6.0L V12, I noticed that there are 2 choices : “emission A” and “all but emission A”
I can’t find which countries are related to which emission class, and what’s the differences between the engines
iirc there are emission class for USA, 1 or 2 in Europe, one for Japan, and probably a few others
any link or suggestion to find out ?
thanks
answering partially my own question , thanks to “the book”
“B emission” (UK and Europe spec) : timer that disables the vacuum advance for 15 minutes after startup if the coolant was below 45°C when started.
“A and C Emission” cars (North America) supplmental air valve, it’s operated for 45 seconds regardless of coolant temp
My car is a Japan market 6.0L, which seems to match the US specs with additional air pump, so is not a B, but I don’t know if it’s either A or C (or something else)
SAV is not the same as AAV or extra air valve :-))
Not only in the book but elsewhere too:
Back to spark plugs. Most likely the choice will be BR6EF or BR7EF.
Either will be OK, regardless of the “emissions market” - fuel formulations have changed quite a bit in the last 1/4 century…
thank(again) Steve
I must learn more about searching, I couldn’t find this subject
The car is currently fitted with BR7EFS which seem to be a small variation of the BR7EF, but I wondered if those were correct
The S-version has a groove. Same temperature rating. Make sure the plugs are gapped to 0.025"
If you re replacing plugs, check the condition of the wires, cap and rotor. If coils have never been replaced in over 25 years, put new ones. All of the above will transform how the car runs.
Good luck!
for the record, I got the following answer from Jaguar (question asked through the jaguar classic parts website)
This vehicle was a Japanese export is not emission A, so part number EBC4021 is required.
EBC4021 being matched to BR6EFS or BR7EFS, as per Steve’s suggestion 
so the Japan export cars were fitted with the same additional air pump, and quad catalysts, but are different from the US cars 
I will have to check if the 6.0L had that many emission versions as the 5.3L, but according to an old Jaguar booklet, at lest the XJ12 had 7 variants, all coded in the VIN
I think the Japanese market required the catalytic converters to have temperature senders and warning light on the dash if the cats are running super hot (misfire) while the US cars were required to have “Check Engine Light”.
In any case, this probably is not very important.
BTW, where are you located xjsv12coupe?
I’m in France, near Paris
yes, the Japan market requires the cat overheat warning system, and this seems a good idea with our Marelli ignition system potential failures
I don’t know if this can be tested , I’ve never seen a warning light for this on the dashboard
I searched for the VIN decoder, and found that 11th character of the VIN is the one about emission control (for this model years)
from http://www.exclusively-jaguar.co.uk/old_site/vins_xjs1.html
1-3 SAJ jaguar
4 J jaguar
5 N model : XJS
6 K class/market : Japan - airbag
7 E body : coupe
8 S engine capacity : 6.0L V12
9 4 steering / transmission : automatic LHD
10 E series : 6 litre XJS
11 P emission control equipment : Australia/Hong Kong 6.0[C]
12-17 xxxxxxxx VIN
the 11th position is a mix of engine, emission class and market , so has many variations
11. Emission Control Equipment *****
C Browns Lane Manufacturing Plant (all markets to 1987)
Emission Control Equipment (all markets from 1987)
A UK/Europe high comp, non-cat 3.6/4.0/5.3[B]
B UK/Europe/Rest of World standard comp, non-cat 3.6[F] 5.3/6.0[B]
C Middle East 3.6/4.0/5.3[D]
E Canada 3.6[E]
F Australia 3.6[D] 5.3[C]
G Austria/Switzerland (to 1988) 3.6[A]
H Japan/Sweden/USA/Switzerland 3.6[A]
J UK/Europe/Japan/Canada/Rest of World 3.6[A] 4.0[C]
K UK/Europe/Rest of World 3.6(non-evap)[A] 4.0/6.0[C]
M Germany 5.3[F]>1989MY UK/Europe 5.3[G]
N Austria 5.3[F]>31/12/88 Switzerland 5.3[F]>1/10/87 UK/Europe 5.3[J] 1991MY>
P Sweden/Norway 5.3[F] USA/Canada 5.3[A] Switzerland 5.3[F]>1/10/87 Austria 5.3[F]1/1/89> Japan/Hong Kong 5.3[D] Australia 5.3[H] Australia/Hong Kong 6.0[C]
R UK/Europe/USA/Canada/Rest of World 6.0[G] Japan 5.3[C]
S USA/Canada/Japan/Stockholm Group 3.6[C] USA 4.0[A]
T Europe 3.6[C] Australia/Hong Kong 4.0[D]
:-))
A lot more characters in the VIN, but the letters in the square brackets at the end are still A through G
BTW, the Book also has a section on VIN decoding:
Mine is SAJNX5344SC199814.
It is a 6.0 liter 1995 coupe. North American spec. Bought and sold in US. I am second owner and know the first.
Wonder which “list” is correct
it seems one J is missing ?
SAJJ
N for XJS
X USA - driver & passenger airbags from 1994 MY***
but the rest doesn’t match any of those
didn’t the US cars had 2 different numbers, one stamped on the body and the other on a sticker ?
(iirc a French owner of a US import had troubles about such US specific numbering)
edit
US cars have a European number, stamped on the firewall, and a US number afixed to the windscreen area
Both numbers have the same suffix (6 digits of the production number , ie 199814 for your car) but the first part differs as US and EUrope have different standards
the SAJNX5344SC199814 is the one on the title, and visible in the windscreen bay
it should match a SAJJNX…SR199814, stamped on the firewall, in the center part below the windscreen, that you can decode using those links
Hi Jim:
Please focus on what the “book” had to say (I included the VIN decoder earlier to show that there is not just emm. A and B)
Here:
Now, if you have a US-spec car, there is a tag within the left edge of the windshield that carries a totally different VIN number. This VIN corresponds to the following scheme, from the “MOTOR import car crash estimating guide” for the US:
1st-3rd Position – Manufacturers Code
SAJ=Jaguar, United Kingdom
4th Position – Model Line
A=XJ6
A=Vanden Plas
C=Sovereign
F=XJ6
H=XJ6, Sovereign
K=Vanden Plas
M=Majestic
M=XJ12
N=XJ-S/XJSC
P=XJR/Sport
S=Jagsport
T=Rouge/Classic
5th Position – Class/Restraint
A=Passive Seat Belt (87-89)
T=Driver Air Bag w/Passive belt
V=Active Seat Belt
W=Driver Air Bag (90-95)
X=Driver & Pass Airbag
Y=North American Spec (83-87)
Y=Passive Seat Belt (89-93)
6th Position – Body Style
1=4 door sedan
2=2+2 Convertible
3=2 door Cabriolet
4=Convertible
5=2 door coupe
7th Position – Engine Code
0=5.3l 12 cyl, Calif.
1=4.0l 6 cyl, Supercharged
2=4.2l 6 cyl, Calif.
3=4.2l 6 cyl
3=6.0l
5=3.6l 6 cyl low compression
6=3.6l 6 cyl high compression
7=4.0l 6 cyl
8=5.3l 12 cyl
9=4.0l 6 cyl
8th Position - Transmission & Steering
4=Automatic (LHS)
8=Manual (LHS)
9th Position - Check Digit
10th Position - MODEL YEAR
D=1983
E=1984
F=1985
G=1986
H=1987
J=1988
K=1989
L=1990
M=1991
N=1992
P=1993
R=1994
S=1995
11th Position - Assembly Plant
C=Browns Lane, England
–
So, based on the Federal VIN, you’ve got:
4th N=XJ-S/XJSC
5th X=Driver & Pass Airbag
6th 5=2 door coupe (mine is 2)
7th 3=6.0l (same as mine)
8th 4=Automatic (LHS) (same as mine)
10th S=1995 (same as mine)
11th Position - C=Browns Lane, England /Assembly Plant
I hope this helps.
Yes Steve.
Guess I was opining that according to which source one uses, you can get a different result and mess with your mind.
Your explanation will serve well in the archives… as your posts usually do.
thanks Steve : the full federal decoding is great information
I updated the thread title to help finding this later
