[v12-engine] Oxymoron: XJR-S and fuel economy

V12-Engine
1

Although it isn’t something I like to dwell on, I have
noticed that the fuel economy of my 1992 XJR-S has recently
dropped. A long motorway run would usually give me 20 mpg
but now I get only 17.

Anything obvious to check myself before I have to troll
around the Jaguar dealerships searching for the last one
with a Zytec ECU diagnostic kit?–
Cosmo - 1992 XJR-S
Surrey, United Kingdom
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2

In reply to a message from Cosmo sent Mon 22 Sep 2008:

How are the Oxygen sensors?–
The original message included these comments:

Anything obvious to check myself before I have to troll
around the Jaguar dealerships searching for the last one
with a Zytec ECU diagnostic kit?

–
Joe Bialy, ’ 87 XJ-S & '04 VDP
Grosse Ile, Michigan, United States
–Posted using Jag-lovers JagFORUM [forums.jag-lovers.org]–
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3

In reply to a message from JaguarJoe sent Mon 22 Sep 2008:

The start up self check reports no problems with the O2
sensors. They were replaced when I bought the car about
30,000 miles ago.–
The original message included these comments:

In reply to a message from Cosmo sent Mon 22 Sep 2008:
How are the Oxygen sensors?

–
Cosmo - 1992 XJR-S
Surrey, United Kingdom
–Posted using Jag-lovers JagFORUM [forums.jag-lovers.org]–
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4

In reply to a message from Cosmo sent Mon 22 Sep 2008:

check the alcohol content of the fuel. The fuel has changed
a lot and has really been a problem on carbs. That can cause
a 3 to 4 MPG loss. Just a thought…–
John Aller www.audietech.com
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5

In reply to a message from doctorpipe sent Mon 22 Sep 2008:

In reply to a message from Cosmo sent Mon 22 Sep 2008

check the alcohol content of the fuel.

Well I had a quick swig, it tasted pretty foul and I
couldn’t detect much alcohol. Maybe a hint of spiced rum?

;-)–
Cosmo - 1992 XJR-S
Surrey, United Kingdom
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6

In reply to a message from Cosmo sent Tue 23 Sep 2008:

My '93 (us spec)xjr-s gets less than that. The best it ever did was
15.8 mpg.–
awa
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7

In reply to a message from awa sent Tue 23 Sep 2008:

My '93 (us spec)xjr-s gets less than that. The best
it ever did was 15.8 mpg.

But that would be US gallons, equivalent to 19.8 mpg in my
damned Imperial measures.–
Cosmo - 1992 XJR-S
Surrey, United Kingdom
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