I have a 78 model XJS and
I just replaced my one wire O2 sensor with a 3 wire sensor. I used a
Bosch 13942 which was about 1/3 the price of the Jag recommended one.
This came about as I failed air care and the car is rich at idle and a
40 km were they test emissions. I have serviced the distributor and
reset all the plugs. I have a 6CU and get 2.49 volts on both banks in
open loop. When I pull the jumper the voltage cycles around 0.8-1.3
volts. Today I am going to make a tool to adjust the pot on the ECU.
Then try air care again.
I there are any other suggestion Please let me known.
This is an 84 XJ-S with 111k KM and the car had only been serviced from
new at the local dealer. I found that the plugs had the wrong gap, the
distributor had been just cleaned and serviced but not the advance
mechcanisium, and the jumped was not connected at the ECU. The list of
approved air care repair shops read like the list of who’s who of not to
use.
Back to work for the next week. Hope to finish of the problem when I
return.
Chuck Mauch
82 XJ12 in a million pieces
84 XJ-S
At 10:18 2001-01-18 -0800, WAVPOWER wrote:
Today I am going to make a tool to adjust the pot on the ECU.
Then try air care again.
I made such a tool:
http://jaguar.professional.org/ECUAdjust/
When adjusting, choose a direction (I like clockwise), and carefully rotate
the adjuster EACH click until full stop, counting each click. Note this
value, because you’ll then be able to return to the original setting if you
cannot get things to work right. Then rotate full stop counterclockwise,
counting the total number of clicks across the range, and then bring it
back to the middle of that (or if you prefer, to the point it was
originally, your choice).
This is an 84 XJ-S with 111k KM and the car had only been serviced from
new at the local dealer. I found that the plugs had the wrong gap,
Common problem - seems many shops (though a Jaguar dealer?) just thought
“oh, same V12 as in the E-type, XJ12, or earlier XJS, and didn’t put any
signifigance to the HE being higher compression (and thus needing a SMALLER
gap). Let me guess, they were gapped at 0.035” or real close to that?
— http://jaguar.professional.org/
Sean Straw '88 Jaguar XJSC 5.3L V12 (LHD) ‘Black Cat’ 63K
Marin County, California '85 Jaguar XJS 5.3L V12 (LHD) ‘Bad Kitty’ 210K
'69 Buick GranSport 455 V8 324K
Check the throttle linkages and an oil change is helpful as well. Plus when
did you last put injector cleaner
in with the gas? If never, fill fresh fuel filer with injector cleaner,
crank over engine with no spark and leave
for a few hours. Results said to be impressive.
I had a similar problem with air care and passed with the above and new
plugs and new air filters.
Roland
'92 XJS
PS Must now change the air valve, crazy term as it actually is driven by
coolant temp.-----Original Message-----
From: owner-xj-s@jag-lovers.org [mailto:owner-xj-s@jag-lovers.org]On
Behalf Of WAVPOWER
Sent: Thursday, January 18, 2001 1:18 PM
To: xj-s@jag-lovers.org
Subject: [xj-s] O2 sensors
I just replaced my one wire O2 sensor with a 3 wire sensor. I used a
Bosch 13942 which was about 1/3 the price of the Jag recommended one.
This came about as I failed air care and the car is rich at idle and a
40 km were they test emissions. I have serviced the distributor and
reset all the plugs. I have a 6CU and get 2.49 volts on both banks in
open loop. When I pull the jumper the voltage cycles around 0.8-1.3
volts. Today I am going to make a tool to adjust the pot on the ECU.
Then try air care again.
I there are any other suggestion Please let me known.
This is an 84 XJ-S with 111k KM and the car had only been serviced from
new at the local dealer. I found that the plugs had the wrong gap, the
distributor had been just cleaned and serviced but not the advance
mechcanisium, and the jumped was not connected at the ECU. The list of
approved air care repair shops read like the list of who’s who of not to
use.
Back to work for the next week. Hope to finish of the problem when I
return.
Chuck Mauch
82 XJ12 in a million pieces
84 XJ-S
replaced the o2’s. i had a 1/2 tank of gas left. milage should have
increased?? i still only went 245 which is the same as before new O2’s. i
went in the trunk and pushed on the white button, i heard no clicks or felt
any kind of “reset”. id10t lite on dash did not come on.[is there one?] just
filled up 20 gals. trip computer is showing 88 o’clock. hard to reset
mile-o-meter. after pushing on it several times it reset. how accurate is
this??? just had ecu rebuilt, new injector harnes, cleaned and lubed dist.
car runs like a raped ape. what else could i check for milage increase???k
& n filters-washed. michael 85 xjs
Andrew:
O2 sensors give a voltage when hot. If you run a voltage meter
from the sensor to ground you should get between 0 and 1 volt.
When the ECU is in control, the signal will be constantly moving
back and forth ( say 0.1 to 0.9 volt).
The O2 sensor is only “in the loop” after the car begins to warm up.
Maybe 2 or 3 minutes after startup. Before that it has no effect.
Output is negligible until the exhaust heats it up.
Richard Drozdowski
1992 XJS-4.0L
I’m in the position of believing that the O2 sensors are faulty on my kitty.
I don’t believe that there is a method of testing them.
I have, however tried to get a resistance reading from them and they both
are ‘open circuit’. Am I correct in thinking that there should be some
resistance there.
As I purchased the car through an estate sale, I’m not sure of the service
history, I’ve owned the car now for about 8 years and only put on approx
1,500 miles. Please advise as I think this may be a possible solution to my
rich mixture problem!
Andrew Benson
'84 XJ-S HE
VIN: SAJNV5848EC
73k miles
Originally a CA car now in Canada
// please trim quoted text to context only
At 09:41 2002-06-26 -0600, Richard Drozdowski wrote:
O2 sensors give a voltage when hot. If you run a voltage meter
from the sensor to ground you should get between 0 and 1 volt.
O2 sensors (“Lambda sensors”) produce a small voltage when in the presence
of oxygen. They operate properly when hot. As you’ve written the
description, it sounds rather like they’re a temp sensor, which isn’t the case.
When the ECU is in control, the signal will be constantly moving
back and forth ( say 0.1 to 0.9 volt).
Whether the ECU is in control or not, the O2 sensor will fluctuating
depending upon the A:F mix and the completeness of burn. In the case of an
EFI car (which is where O2 sensors are employed ), the ECU obviously has
to be operating in order for the engine to run at all (those pesky
injectors need to be triggered after all). However, even if the ECU is
open loop (not paying attention to the O2 sensors), the O2 sensors will be
fluctuating - just not in the same rhythm as when the ECU is in closed loop
constantly adjusting fuel mixture.
I assume that Andrew wrote, in a message having a different subject header:
I’m in the position of believing that the O2 sensors are faulty on my kitty.
I don’t believe that there is a method of testing them.
Not so - you can easily make a tee connector (or use a good hook probe, but
a tee works well) - one wire that runs from your metre +V (red lead) input
up to an insulated 0.25" spade, and from there to a mating (opposite
gender) insulated 0.25" spade:
]]=-----------------------=##
\
\
\ (metre)
(the tee point could really be anywhere along that wire, but right at the
point where the spade connects is easiest from an assembly standpoint)
Then, remove the outer half of the air cleaner shell on the side you’re
testing and reach down and disconnect the O2 signal wire, and plug this
wire in between. Connect your metre or scope (this works really well with
a scope) to the tap wire, and the other (GND) lead of the metre/scope out
to a chassis ground. This requires a high inductance metre - your great
grandpappy’s little needle type metre isn’t a good idea here. A digital
metre, while it should have a high inductance, may not register the signal
rapidly enough for you to see a change is occurring. A scope WILL be high
inductance, and will show the pattern of the up and down voltage.
Run the car to operating temperature, then check out the signal. Note that
if you’re in Neutral or Park (which is pretty likely ), you’ll need to
disconnect the shorting plug on the wire coming from the ECU in the boot -
that will force the ECU into closed loop even when the car is in N/P
(otherwise, it runs off of a fuelling map).
Check my website for info on my O2 replacement - there are various O2
sensor links from there. Also, check the XJ-S and V12 list archives -
you’re certainly not the first person looking for info on how to test, and
there’s a great deal of information already written about these devices on
these forums. You’ll also find some extended discussions of scopes circa
fall of last year (don’t be daunted by the apparent complexity of a scope -
you can pick up a secondhand scope off of eBay for < US$100, and you don’t
need a high speed one for automotive diagnostics).
I have, however tried to get a resistance reading from them and they both
are ‘open circuit’. Am I correct in thinking that there should be some
resistance there.
That isn’t how you test them.
— http://jaguar.professional.org/
Sean Straw '88 Jaguar XJSC 5.3L V12 (LHD) ‘Black Cat’ 65K
Marin County, California '85 Jaguar XJS 5.3L V12 (LHD) ‘Bad Kitty’ 210K
'69 Buick GranSport 455 V8 324K
// please trim quoted text to context only
fall of last year (don’t be daunted by the apparent complexity of a scope -
you can pick up a secondhand scope off of eBay for < US$100, and you don’t
need a high speed one for automotive diagnostics).
Radioshack puts out a multimeter (for about $85) with a RS232 port to use
your computer as an oscillioscope-not sure abot the sampling rate though.
I haven’t used this feature since I haven’t a garage-apt. people aren’t
crazy about auto work either so I take it elsewhere.
-Rob-
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Hello,
I would like to know how to tell if my O2 sensors need replacing. I
am starting to get hesitation and sputtering at low RPMs when the
engine is cool.
Where are the sensors located and do I need a special tool to
remove them?
I have a 1996, XJS, 6 cylinder, 4.0 liter with 47,000 miles.
Regards
EBJ–
ebjco
–Posted using Jag-lovers JagFORUM [forums.jag-lovers.org]–
// please trim quoted text to context only
In reply to a message from ebjco sent Fri 16 Jul 2004:
they are basically right inside of front wheels. You will need an
O2 sensor tool which can be picked up at an auto parts store for a
couple bucks.–
The original message included these comments:
Where are the sensors located and do I need a special tool to
remove them?
–
Rory in Seattle with his 1990 Xjs V12 Coupe
–Posted using Jag-lovers JagFORUM [forums.jag-lovers.org]–
// please trim quoted text to context only
I will look up the voltage output tonight.
Keep in mind you have to install the O2 sensors in the
correct order. There are 4 to replace. Front Right
(FR), FL, Rear Right (RR), RL. They measure the
before and after O2 and the ECU adjusts engine
perameters. If you mix the wires/sensors up you have
to go to the dealer to have the ECU reprogrammed.— ebjco ebjco1@yahoo.com wrote:
Hello,
I would like to know how to tell if my O2 sensors
need replacing. I
am starting to get hesitation and sputtering at low
RPMs when the
engine is cool.I have a 1996, XJS, 6 cylinder, 4.0 liter with
47,000 miles.
=====
Geoff Green
95 XJS 4.0 conv 61 E-type OTS
International Cabriolet Register Jag92hot@aol.com
3.6 XJS Register paulzimmer@btopenworld.com
// please trim quoted text to context only
Hey ebjco,
The output for the sensors is between 3.3V for lean
and 1.1V for rich.
No check engine light. It passed it’s emission test
last week when I went for my inspection test. I had
it up to 100 MPH the other day, no problem. It only
seems to hesitate when the engine is cool.
// please trim quoted text to context only
O2 sensor voltage will never be higher than 1.1 volts unless it is
shorted across the heater circuit.
John Robison
EOP1 Development Engineer - Oxygen Sensors
e-mail: john.robison@us.bosch.com
Phone: (864) 260-8689
Page: (877) 509-6219
Fax: (864) 260-8118-----Original Message-----
From: owner-xj-s@jag-lovers.org [mailto:owner-xj-s@jag-lovers.org] On
Behalf Of Geoffrey Green
Sent: Friday, July 16, 2004 11:28 PM
To: xj-s
Subject: Re: [xj-s] O2 sensors
Hey ebjco,
The output for the sensors is between 3.3V for lean
and 1.1V for rich.
No check engine light. It passed it’s emission test
last week when I went for my inspection test. I had
it up to 100 MPH the other day, no problem. It only
seems to hesitate when the engine is cool.
// please trim quoted text to context only
// please trim quoted text to context only
Hello Everyone,
Could someone tell how many O2 sensors are on a 95 AJ16 engine and their
location.Thanks.
Larry
95xj-s 2+2
98XJ8VP
// please trim quoted text to context only
In reply to a message from larry doyon sent Sun 7 Nov 2004:
I would say ONE (though some vehicles do use 2!) in the exhaust
system UPSTREAM of the catalytic converter. Get under your car,
locate the cat and where the exhaust pipe enters the cat follow it
towards the engine and where you see a sensor screwed into the pipe
or exhaust manifold downpipe THAT is your oxygen sensor. Be sure to
check that your car does or does not have 2.
Regards,
Roger–
rogerlaf
Sutton, Massachusetts, United States
–Posted using Jag-lovers JagFORUM [forums.jag-lovers.org]–
–Support Jag-lovers - Donate at http://www.jag-lovers.org/donate04.php –
// please trim quoted text to context only
Larry,
There are four (4) O2 sensors. Two per down pipe.
These are Nippon Denso 4 wire sensors.
Be careful! You cannot mix the location. Otherwise
you will need a trip to the dealer to re-program the
ECU. Two measure the exhaust before the cat and two
measure the exhaust after the cat. So you have front
cylinders pre-cat, front cylinders after-cat, rear
cylinders pre-cat, rear cylinders after-cat. Label
the harness wires before removal. Or change one at a
time.
Use anti-seize compound.— larry doyon leap4l@pennswoods.net wrote:
Hello Everyone,
Could someone tell how many O2 sensors are on a 95
AJ16 engine and their
location.Thanks.
Larry
95xj-s 2+2
98XJ8VP
=====
Geoff Green
95 XJS 4.0 conv 61 E-type OTS
International Cabriolet Register Jag92hot@aol.com
3.6 XJS Register paulzimmer@btopenworld.com
// please trim quoted text to context only
For what it’s worth, Advance Auto, and others I’m sure, have an inexpensive 3
wire replacement for the XJ-S. Bosch 13942. NAPA 3259 o2 tool is a very deep
socket and (with acetylene) makes the job a snap. Requires splicing wires.
Total cost about $105.00 (NA)
Ellwood Brown soon to be ex-XJ-S coupe
// please trim quoted text to context only
In reply to a message from EBrown5660@aol.com sent Mon 6 Dec 2004:
A crows foot socket works without cutting wires,also Standard Auto
Parts overs original O2 for 97.99 US plugs right in #SG247–
bob stacey
–Posted using Jag-lovers JagFORUM [forums.jag-lovers.org]–
–Support Jag-lovers - Donate at http://www.jag-lovers.org/donate04.php –
// please trim quoted text to context only
In reply to a message from EBrown5660@aol.com sent Mon 6 Dec 2004:
A crows foot socket works without cutting wires,also Standard Auto
Parts overs original O2 for 97.99 US plugs right in #SG247–
bob stacey
–Posted using Jag-lovers JagFORUM [forums.jag-lovers.org]–
–Support Jag-lovers - Donate at http://www.jag-lovers.org/donate04.php –
// please trim quoted text to context only
I got 3wire O2 sensors from that subsidiary of NGK (something like NKT)
for a 1988 V12 that plugged right in with no splicing.
Afton.
bob stacey wrote:
In reply to a message from EBrown5660@aol.com sent Standard Auto
Parts overs original O2 for 97.99 US plugs right in #SG247
// please trim quoted text to context only