Question about 1986 Jaguar XJSC

1 Answer

1989 jaguar xjs v12 fuel mixture

My xjs is burnning rich and missing. I pulled the plugs I could get to and they are heavly carboned I cleand three and the car ran good for about 5 miles then back to running bad can anyone help
thanks

Posted by on

1 Answer

  • Level 1:

    An expert who has achieved level 1.

  • Contributor
  • 1 Answer

Chances are the coolant temperature sensor or its wiring have failed, or the vacuum line to the MAP sensor is leaky or broken (I believe the V12 in '89 guise uses MAP sensors). The MAP sensor measures Manifold Absolute Pressure. Along with this pressure the ECU looks at engine RPM. It also measures air temperature. Knowing pressure and temperature we know density, and knowing engine speed tells us how much volume of air is going through the engine. All of this together is computed into air mass and is used to calculate how much fuel mass should be admitted. If the vacuum line is broken, the ECU reads less vacuum and produces rich mixture thinking that the engine is under high load.

Posted on Dec 27, 2008

Add Your Answer

Uploading: 0%

my-video-file.mp4

Complete. Click "Add" to insert your video. Add

×

Loading...
Loading...

Related Questions:

1 Answer

Qhere do i find the coolant temp sensor an the map swnsor


Jaguar Sensor, XJ6, XJ8, XJS, XK8, S-TYPE, X-TYPE, XJ40 ...

www.jagbits.com/jaguarsensor.php
FITS: 1993-1994 6.0 XJ12 AND 1989-1993 V12 XJS FROM VIN 157118 ON, 1994-1996 6.0 V12 XJS FRONT DAMPER .... LNA1622AA - MAP SENSOR ... C42166-USED - USED SENSOR COOLANT TEMPERATURE FOR FUEL INJECTION

Sep 25, 2015 | Cars & Trucks

1 Answer

Why does idle speed surge?


Thread: 6.0 V12 XJS High RPM When Warm - Jaguar Forum.co.uk

www.jaguarforum.com/showthread.php?t=54266
Mar 3, 2013 - I recently bought a 1993 6.0 V12 XJS and when it is started from cold it runs ... to 1300 RPM so it wants to surge forward when braking which is strange. ...Classics ยท XJS 3.6,4.0,5.3 & 6.0; 6.0 V12 XJS High RPM When Warm ... You might want to adjust the aux (extra) air valve to bring the idle speed down.

Sep 25, 2015 | 1989 Jaguar XJS 5.3

1 Answer

HOW TO FREE UP A STUCK VALVE ON MY V12


Doubtful the valve is "stuck". More likely to be burnt. It happens. Do a compression check then pull the head off and replace the valve that is losing compression.

Aug 26, 2014 | 1989 Jaguar XJS 5.3

1 Answer

Where is the fuel filter location for a 1994 jaguar XJS 6,0 V12?


next to the tank at the top of the body under neath. or on the updated version engine bay follow the fuel line and it goes into a contaner with 2 pipes on it that is the filter.

Oct 16, 2013 | Jaguar XJS Cars & Trucks

1 Answer

Xjs belt routing v12 6 litre


1) yes the belt missing time, is critical , the motor will not Start , you must go to some repair shop.

God bless you

Jun 27, 2012 | Cars & Trucks

1 Answer

How many miles will you get out of the v12 motor in a 1989 xjs? Im looking to buy one but it has 250000km on the clock


I would get complete set of maintenance records for that one. 250k is alot for a jag especially a V12. That one is either running on borrowed time or has been meticulously taken care of.

Mar 31, 2011 | Jaguar XJS Cars & Trucks

1 Answer

I am trying to locate the chrome LHS door mirror for 1989/90 XJS 5.3 V12


jaguar owners club.co.uk will be able to assist (if its just the glass get some cut locally.use double sided carpet tape to stick it on over the old))

Oct 04, 2010 | 1989 Jaguar XJ6

1 Answer

Cant start my 89 v12 xjs


Replace the crank sensor under engine. 90% of the problems is here.
Einar Norway

Dec 13, 2008 | 1986 Jaguar XJSC

1 Answer

1989 XJS V12 furl problem


Obviously, fuel and oil should never be in the same spot at the same time. You have a dead cylinder and maybe a stuck-open injector. The black smoke is from a too-rich fuel mix, so the cheap things to look for are in the fuel injection system. Look at the fuel pressure regulator as well. Good luck, and don't forget to relieve the fuel pressure before you do any work on fuel inj. engines!

Jul 28, 2008 | 1984 Jaguar XJ

Not finding what you are looking for?
Cars & Trucks Logo

Related Topics:

1,065 people viewed this question

Ask a Question

Usually answered in minutes!

Top Jaguar Experts

Colin Stickland
Colin Stickland

Level 3 Expert

21949 Answers

Raygin
Raygin

Level 2 Expert

322 Answers

yadayada
yadayada

Level 3 Expert

61037 Answers

Are you a Jaguar Expert? Answer questions, earn points and help others

Answer questions

Manuals & User Guides

Loading...