[modern] Engine idle "Hunting"

To Modern Specialists (like Brett G.)

 Car idles at a higher idle than normal at start-up. Then begins to rev 
 and un-rev. Is this the previously mentioned "hunting problem" from  
 the archives? Why does pressing the brake seem to effect it?
 Anyway after switching the engine on and off again it went away. 
 I was wondering if the EGR valve could have stuck momentarily. 
 As always any help- much appreciated. Also car still 
 occasionally jumps/slips out of first gear on a 90 degree curve. 
  
 
 Rich in San Diego
 '90 XJ40 VDP 134K miles.

Rich,
If the base idle is off, the CPU will work the ISCV to try to correct
it(hence the hunting).

The brake pedal should not have any effect on the idle at any time…
and I don’t know how it could possibly, other than some weird
cruse control problem.

You should clean and inspect the ISCV while setting the base idle,
as well as clean out the crankcase vent stuff.

As for the transmission problem, its surely fluid level related…
You may have the aftermarket trans filter with the pickup on the side
of the filter, instead of the Jaguar style with the spout out the bottom.
I would remove the pan and check it.
I would suspect it would be worse turning in one direction, as the
inlet is on one side of the filter…left side I think…so left turns
would put the fluid into the right side of the pan.

While the fram filter fit, I cleaned and re used the Jaguar filter
with the spout…the filter is just a fine screen…the magnets
in the pan do the actual filtering.

Brett
1990 XJ6
…Date: Wed, 24 May 2000 14:45 -0700
From: rrobinso rrobinso@viasat.com
Subject: [modern] Engine idle “Hunting”
Sender: owner-modern@jag-lovers.org
To: "modern@jag-lovers.org" modern@jag-lovers.org
Message-id: 20000524144930214-66a75d5e@viasat.com

 To Modern Specialists (like Brett G.)
 
 Car idles at a higher idle than normal at start-up. Then begins to rev 
 and un-rev. Is this the previously mentioned "hunting problem" from  
 the archives? Why does pressing the brake seem to effect it?
 Anyway after switching the engine on and off again it went away. 
 I was wondering if the EGR valve could have stuck momentarily. 
 As always any help- much appreciated. Also car still 
 occasionally jumps/slips out of first gear on a 90 degree curve. 
  
 
 Rich in San Diego
 '90 XJ40 VDP 134K miles.

Rich,

sounds like you need to clean the throttle body and reset the base idle. May
be worth cleaning the ISCV itself with catalyst friendly carb cleaner as
well.

I guess the brakes could affect it if you have a set up using manifold
vacuum for power assist - I think some models had this system, though my '91
has the electric pump set up.

Cheers - Jez>-----Original Message-----

From: rrobinso [mailto:rrobinso@viasat.com]
Sent: 24 May 2000 22:45
To: modern@jag-lovers.org
Subject: [modern] Engine idle “Hunting”

To Modern Specialists (like Brett G.)

Car idles at a higher idle than normal at start-up. Then

begins to rev
and un-rev. Is this the previously mentioned “hunting problem” from
the archives? Why does pressing the brake seem to effect it?
Anyway after switching the engine on and off again it went away.
I was wondering if the EGR valve could have stuck momentarily.
As always any help- much appreciated. Also car still
occasionally jumps/slips out of first gear on a 90 degree curve.

Rich in San Diego
'90 XJ40 VDP 134K miles.

To Modern Jag List,

 I've just been catching up on my reading of the modern digest. Someone 
 mentioned the lightning bolt indicating a fuse failure. My VCM says I 
 have fuse 2 and fuse 6 fail. I caused the fuse 2 failure myself to 
 keep my driver's side belt from sticking in mid-slide position and 
 thus draining the battery. But I can't find anything
 on a fuse 6 failure in the archives. If anyone (Brett) knows what this 
 indicates, or where this fuse is located I would be grateful. No luck
 searching the archives for fuse 6. My AC doesn't appear to be getting 
 cold so I thought it might be suspect. 
                                        A note on the fuse 2 fail.
  I know it is warranted for the life of the car. But I am hesitant
 to let the local dealer work on my cat. They take it out of sight to 
 some dark place out of reach where I can't see it or hear it. I am 
 afraid that they are doing something sinister. My Jag always lets me
 know when it is upset after I leave it with someone. The last time I 
 did this my rear windows refused to go up with the driver's door 
 switch and still do. Of course it could be because the mechanic left
 the car out in the rain with the front windows open.
    
 
                   
 
 
 Rich in San Diego
 '90 XJ40 VDP 134K miles.

What is the large metal box with cooling fins just forward of
the driver’s (US) side lamp module in the trunk? It is large and
‘unpainted aluminum’ in color.
I found it while searching for the
elusive ‘American Jaguar AC relay’ which is usually nocturnal
and only shows itself on the hottest days of summer and uses the
trunk (boot) carpet for camouflage. I remember sighting one back
in '97 but I can’t quite remember where.

 Rich in San Diego
 '90 XJ40 VDP 134K miles.

Rich,

I think the box you refer to is an old mobile phone installation.

Ron Mewett
'89 XJ6 vdp
97K miles-----Original Message-----
From: owner-modern@jag-lovers.org [mailto:owner-modern@jag-lovers.org]On
Behalf Of rrobinso
Sent: Friday, August 25, 2000 2:15 PM
To: modern@jag-lovers.org
Subject: [modern] Engine idle “Hunting”

 What is the large metal box with cooling fins just forward of 
 the driver's (US) side lamp module in the trunk? It is large and 
 'unpainted aluminum' in color.                                   
                               I found it while searching for the 
 elusive 'American Jaguar AC relay'  which is usually nocturnal 
 and only shows itself on the hottest days of summer and uses the
 trunk (boot) carpet for camouflage. I remember sighting one back
 in '97 but I can't quite remember where.
  
 
 
 
 
 
 
 
 Rich in San Diego
 '90 XJ40 VDP 134K miles.

ABS computer.Date: Fri, 25 Aug 2000 14:15 -0700
From: rrobinso rrobinso@viasat.com
Subject: [modern] Engine idle “Hunting”
Sender: owner-modern@jag-lovers.org
To: "modern@jag-lovers.org" modern@jag-lovers.org

 What is the large metal box with cooling fins just forward of 
 the driver's (US) side lamp module in the trunk? It is large and 
 'unpainted aluminum' in color.                                   
                               I found it while searching for the 
 elusive 'American Jaguar AC relay'  which is usually nocturnal 
 and only shows itself on the hottest days of summer and uses the
 trunk (boot) carpet for camouflage. I remember sighting one back
 in '97 but I can't quite remember where.
  
 
 
 
 
 
 
 
 Rich in San Diego
 '90 XJ40 VDP 134K miles.

cooling fins ? I’d say some kind of stereo amplifier ?

Pascal
Miami, FL----- Original Message -----
From: “Ron Mewett” mewett@msn.com
To: modern@jag-lovers.org
Sent: Friday, August 25, 2000 6:18 PM
Subject: [modern] RE: Metal box in boot

Rich,

I think the box you refer to is an old mobile phone installation.

Ron Mewett
'89 XJ6 vdp
97K miles

-----Original Message-----
From: owner-modern@jag-lovers.org [mailto:owner-modern@jag-lovers.org]On
Behalf Of rrobinso
Sent: Friday, August 25, 2000 2:15 PM
To: modern@jag-lovers.org
Subject: [modern] Engine idle “Hunting”

 What is the large metal box with cooling fins just forward of 
 the driver's (US) side lamp module in the trunk? It is large and 
 'unpainted aluminum' in color.                                   
                               I found it while searching for the 
 elusive 'American Jaguar AC relay'  which is usually nocturnal 
 and only shows itself on the hottest days of summer and uses the
 trunk (boot) carpet for camouflage. I remember sighting one back
 in '97 but I can't quite remember where.
  
 
 
 
 
 
 
 
 Rich in San Diego
 '90 XJ40 VDP 134K miles.