XJ stumble, check engine light
#21
Guest
Posts: n/a
Re: XJ stumble, check engine light
The procedure is outlined here or if you stop by almost any auto-parts store
they will lend you a lend you a reader at no charge or they may read it for
you if they are not busy.
http://www.ptcruizer.com/computer-codes.html
If you send me an e-address I'll forward the appropriate FSM data to you.
"twaldron" <thomasOBVIOUS@rubicons.com> wrote in message
news:wsy%f.1515$Lm5.1043@newssvr12.news.prodigy.co m...
> Yes, it would. I don't have a reader, so I'm looking to try a few common
> things prior to paying for a service visit.
>
> tw
> __________________________________________________ ___________________
> 2003 TJ Rubicon * 2001 XJ Sport * 1971 Bill Stroppe Baja Bronco
>
> "There is a very fine line between 'hobby' and 'mental illness'."
>
> Pronunciation: 'jEp Function: noun Date: 1940
>
> Etymology: from g. p. (G= 'Government' P= '80 inch wheelbase')
> A small general-purpose motor vehicle with 80" wheelbase, 1/4-ton
> capacity and four-wheel drive used by the U.S. army in World War II.
> __________________________________________________ ___________________
>
> Billy Ray wrote:
> > Well.... it would be best to know what the code is this time even though
the
> > symptons are similar.
> >
> > "twaldron" <thomasOBVIOUS@rubicons.com> wrote in message
> > news:20x%f.1484$Lm5.141@newssvr12.news.prodigy.com ...
> >
> >>I haven't had the error checked this time for a code, but the problem is
> >>exactly like last time. I'm pretty sure the code was P0300 last time.
> >>
> >>tw
> >>________________________________________________ _____________________
> >>2003 TJ Rubicon * 2001 XJ Sport * 1971 Bill Stroppe Baja Bronco
> >>
> >>"There is a very fine line between 'hobby' and 'mental illness'."
> >>
> >>Pronunciation: 'jEp Function: noun Date: 1940
> >>
> >>Etymology: from g. p. (G= 'Government' P= '80 inch wheelbase')
> >>A small general-purpose motor vehicle with 80" wheelbase, 1/4-ton
> >>capacity and four-wheel drive used by the U.S. army in World War II.
> >>________________________________________________ _____________________
> >>
> >>
> >>Billy Ray wrote:
> >>
> >>>What code?
> >>>
> >>>"twaldron" <thomasOBVIOUS@rubicons.com> wrote in message
> >>>news:H8u%f.1405$Lm5.1220@newssvr12.news.prodigy .com...
> >>>
> >>>
> >>>>This is the second time this has happened, otherwise the Jeep runs
> >>>>great. Once at about 15k miles and this time at about 50k miles, upon
> >>>>cold starting, the engine stumbles (of course no gas pedal), runs
really
> >>>>rough for about 20-30 seconds, then planes out. This triggers the
CHECK
> >>>>ENGINE light. The vehicle runs fine after that, but the light stays
on.
> >>>>The first time, the dealer reset the light during a visit for a brake
> >>>>rotor issue, but found no problems. Gas cap OK, both times.
Suggestions?
> >>>>
> >>>>tw
> >>>>--
> >>>>______________________________________________ _______________________
> >>>>2003 TJ Rubicon * 2001 XJ Sport * 1971 Bill Stroppe Baja Bronco
> >>>>
> >>>>"There is a very fine line between 'hobby' and 'mental illness'."
> >>>>
> >>>>Pronunciation: 'jEp Function: noun Date: 1940
> >>>>
> >>>>Etymology: from g. p. (G= 'Government' P= '80 inch wheelbase')
> >>>>A small general-purpose motor vehicle with 80" wheelbase, 1/4-ton
> >>>>capacity and four-wheel drive used by the U.S. army in World War II.
> >>>>______________________________________________ _______________________
> >>>
> >>>
> >>>
> >
> >
they will lend you a lend you a reader at no charge or they may read it for
you if they are not busy.
http://www.ptcruizer.com/computer-codes.html
If you send me an e-address I'll forward the appropriate FSM data to you.
"twaldron" <thomasOBVIOUS@rubicons.com> wrote in message
news:wsy%f.1515$Lm5.1043@newssvr12.news.prodigy.co m...
> Yes, it would. I don't have a reader, so I'm looking to try a few common
> things prior to paying for a service visit.
>
> tw
> __________________________________________________ ___________________
> 2003 TJ Rubicon * 2001 XJ Sport * 1971 Bill Stroppe Baja Bronco
>
> "There is a very fine line between 'hobby' and 'mental illness'."
>
> Pronunciation: 'jEp Function: noun Date: 1940
>
> Etymology: from g. p. (G= 'Government' P= '80 inch wheelbase')
> A small general-purpose motor vehicle with 80" wheelbase, 1/4-ton
> capacity and four-wheel drive used by the U.S. army in World War II.
> __________________________________________________ ___________________
>
> Billy Ray wrote:
> > Well.... it would be best to know what the code is this time even though
the
> > symptons are similar.
> >
> > "twaldron" <thomasOBVIOUS@rubicons.com> wrote in message
> > news:20x%f.1484$Lm5.141@newssvr12.news.prodigy.com ...
> >
> >>I haven't had the error checked this time for a code, but the problem is
> >>exactly like last time. I'm pretty sure the code was P0300 last time.
> >>
> >>tw
> >>________________________________________________ _____________________
> >>2003 TJ Rubicon * 2001 XJ Sport * 1971 Bill Stroppe Baja Bronco
> >>
> >>"There is a very fine line between 'hobby' and 'mental illness'."
> >>
> >>Pronunciation: 'jEp Function: noun Date: 1940
> >>
> >>Etymology: from g. p. (G= 'Government' P= '80 inch wheelbase')
> >>A small general-purpose motor vehicle with 80" wheelbase, 1/4-ton
> >>capacity and four-wheel drive used by the U.S. army in World War II.
> >>________________________________________________ _____________________
> >>
> >>
> >>Billy Ray wrote:
> >>
> >>>What code?
> >>>
> >>>"twaldron" <thomasOBVIOUS@rubicons.com> wrote in message
> >>>news:H8u%f.1405$Lm5.1220@newssvr12.news.prodigy .com...
> >>>
> >>>
> >>>>This is the second time this has happened, otherwise the Jeep runs
> >>>>great. Once at about 15k miles and this time at about 50k miles, upon
> >>>>cold starting, the engine stumbles (of course no gas pedal), runs
really
> >>>>rough for about 20-30 seconds, then planes out. This triggers the
CHECK
> >>>>ENGINE light. The vehicle runs fine after that, but the light stays
on.
> >>>>The first time, the dealer reset the light during a visit for a brake
> >>>>rotor issue, but found no problems. Gas cap OK, both times.
Suggestions?
> >>>>
> >>>>tw
> >>>>--
> >>>>______________________________________________ _______________________
> >>>>2003 TJ Rubicon * 2001 XJ Sport * 1971 Bill Stroppe Baja Bronco
> >>>>
> >>>>"There is a very fine line between 'hobby' and 'mental illness'."
> >>>>
> >>>>Pronunciation: 'jEp Function: noun Date: 1940
> >>>>
> >>>>Etymology: from g. p. (G= 'Government' P= '80 inch wheelbase')
> >>>>A small general-purpose motor vehicle with 80" wheelbase, 1/4-ton
> >>>>capacity and four-wheel drive used by the U.S. army in World War II.
> >>>>______________________________________________ _______________________
> >>>
> >>>
> >>>
> >
> >
#22
Guest
Posts: n/a
Re: XJ stumble, check engine light
The procedure is outlined here or if you stop by almost any auto-parts store
they will lend you a lend you a reader at no charge or they may read it for
you if they are not busy.
http://www.ptcruizer.com/computer-codes.html
If you send me an e-address I'll forward the appropriate FSM data to you.
"twaldron" <thomasOBVIOUS@rubicons.com> wrote in message
news:wsy%f.1515$Lm5.1043@newssvr12.news.prodigy.co m...
> Yes, it would. I don't have a reader, so I'm looking to try a few common
> things prior to paying for a service visit.
>
> tw
> __________________________________________________ ___________________
> 2003 TJ Rubicon * 2001 XJ Sport * 1971 Bill Stroppe Baja Bronco
>
> "There is a very fine line between 'hobby' and 'mental illness'."
>
> Pronunciation: 'jEp Function: noun Date: 1940
>
> Etymology: from g. p. (G= 'Government' P= '80 inch wheelbase')
> A small general-purpose motor vehicle with 80" wheelbase, 1/4-ton
> capacity and four-wheel drive used by the U.S. army in World War II.
> __________________________________________________ ___________________
>
> Billy Ray wrote:
> > Well.... it would be best to know what the code is this time even though
the
> > symptons are similar.
> >
> > "twaldron" <thomasOBVIOUS@rubicons.com> wrote in message
> > news:20x%f.1484$Lm5.141@newssvr12.news.prodigy.com ...
> >
> >>I haven't had the error checked this time for a code, but the problem is
> >>exactly like last time. I'm pretty sure the code was P0300 last time.
> >>
> >>tw
> >>________________________________________________ _____________________
> >>2003 TJ Rubicon * 2001 XJ Sport * 1971 Bill Stroppe Baja Bronco
> >>
> >>"There is a very fine line between 'hobby' and 'mental illness'."
> >>
> >>Pronunciation: 'jEp Function: noun Date: 1940
> >>
> >>Etymology: from g. p. (G= 'Government' P= '80 inch wheelbase')
> >>A small general-purpose motor vehicle with 80" wheelbase, 1/4-ton
> >>capacity and four-wheel drive used by the U.S. army in World War II.
> >>________________________________________________ _____________________
> >>
> >>
> >>Billy Ray wrote:
> >>
> >>>What code?
> >>>
> >>>"twaldron" <thomasOBVIOUS@rubicons.com> wrote in message
> >>>news:H8u%f.1405$Lm5.1220@newssvr12.news.prodigy .com...
> >>>
> >>>
> >>>>This is the second time this has happened, otherwise the Jeep runs
> >>>>great. Once at about 15k miles and this time at about 50k miles, upon
> >>>>cold starting, the engine stumbles (of course no gas pedal), runs
really
> >>>>rough for about 20-30 seconds, then planes out. This triggers the
CHECK
> >>>>ENGINE light. The vehicle runs fine after that, but the light stays
on.
> >>>>The first time, the dealer reset the light during a visit for a brake
> >>>>rotor issue, but found no problems. Gas cap OK, both times.
Suggestions?
> >>>>
> >>>>tw
> >>>>--
> >>>>______________________________________________ _______________________
> >>>>2003 TJ Rubicon * 2001 XJ Sport * 1971 Bill Stroppe Baja Bronco
> >>>>
> >>>>"There is a very fine line between 'hobby' and 'mental illness'."
> >>>>
> >>>>Pronunciation: 'jEp Function: noun Date: 1940
> >>>>
> >>>>Etymology: from g. p. (G= 'Government' P= '80 inch wheelbase')
> >>>>A small general-purpose motor vehicle with 80" wheelbase, 1/4-ton
> >>>>capacity and four-wheel drive used by the U.S. army in World War II.
> >>>>______________________________________________ _______________________
> >>>
> >>>
> >>>
> >
> >
they will lend you a lend you a reader at no charge or they may read it for
you if they are not busy.
http://www.ptcruizer.com/computer-codes.html
If you send me an e-address I'll forward the appropriate FSM data to you.
"twaldron" <thomasOBVIOUS@rubicons.com> wrote in message
news:wsy%f.1515$Lm5.1043@newssvr12.news.prodigy.co m...
> Yes, it would. I don't have a reader, so I'm looking to try a few common
> things prior to paying for a service visit.
>
> tw
> __________________________________________________ ___________________
> 2003 TJ Rubicon * 2001 XJ Sport * 1971 Bill Stroppe Baja Bronco
>
> "There is a very fine line between 'hobby' and 'mental illness'."
>
> Pronunciation: 'jEp Function: noun Date: 1940
>
> Etymology: from g. p. (G= 'Government' P= '80 inch wheelbase')
> A small general-purpose motor vehicle with 80" wheelbase, 1/4-ton
> capacity and four-wheel drive used by the U.S. army in World War II.
> __________________________________________________ ___________________
>
> Billy Ray wrote:
> > Well.... it would be best to know what the code is this time even though
the
> > symptons are similar.
> >
> > "twaldron" <thomasOBVIOUS@rubicons.com> wrote in message
> > news:20x%f.1484$Lm5.141@newssvr12.news.prodigy.com ...
> >
> >>I haven't had the error checked this time for a code, but the problem is
> >>exactly like last time. I'm pretty sure the code was P0300 last time.
> >>
> >>tw
> >>________________________________________________ _____________________
> >>2003 TJ Rubicon * 2001 XJ Sport * 1971 Bill Stroppe Baja Bronco
> >>
> >>"There is a very fine line between 'hobby' and 'mental illness'."
> >>
> >>Pronunciation: 'jEp Function: noun Date: 1940
> >>
> >>Etymology: from g. p. (G= 'Government' P= '80 inch wheelbase')
> >>A small general-purpose motor vehicle with 80" wheelbase, 1/4-ton
> >>capacity and four-wheel drive used by the U.S. army in World War II.
> >>________________________________________________ _____________________
> >>
> >>
> >>Billy Ray wrote:
> >>
> >>>What code?
> >>>
> >>>"twaldron" <thomasOBVIOUS@rubicons.com> wrote in message
> >>>news:H8u%f.1405$Lm5.1220@newssvr12.news.prodigy .com...
> >>>
> >>>
> >>>>This is the second time this has happened, otherwise the Jeep runs
> >>>>great. Once at about 15k miles and this time at about 50k miles, upon
> >>>>cold starting, the engine stumbles (of course no gas pedal), runs
really
> >>>>rough for about 20-30 seconds, then planes out. This triggers the
CHECK
> >>>>ENGINE light. The vehicle runs fine after that, but the light stays
on.
> >>>>The first time, the dealer reset the light during a visit for a brake
> >>>>rotor issue, but found no problems. Gas cap OK, both times.
Suggestions?
> >>>>
> >>>>tw
> >>>>--
> >>>>______________________________________________ _______________________
> >>>>2003 TJ Rubicon * 2001 XJ Sport * 1971 Bill Stroppe Baja Bronco
> >>>>
> >>>>"There is a very fine line between 'hobby' and 'mental illness'."
> >>>>
> >>>>Pronunciation: 'jEp Function: noun Date: 1940
> >>>>
> >>>>Etymology: from g. p. (G= 'Government' P= '80 inch wheelbase')
> >>>>A small general-purpose motor vehicle with 80" wheelbase, 1/4-ton
> >>>>capacity and four-wheel drive used by the U.S. army in World War II.
> >>>>______________________________________________ _______________________
> >>>
> >>>
> >>>
> >
> >
#23
Guest
Posts: n/a
Re: XJ stumble, check engine light
fault codes are?????
twaldron wrote:
> This is the second time this has happened, otherwise the Jeep runs
> great. Once at about 15k miles and this time at about 50k miles, upon
> cold starting, the engine stumbles (of course no gas pedal), runs really
> rough for about 20-30 seconds, then planes out. This triggers the CHECK
> ENGINE light. The vehicle runs fine after that, but the light stays on.
> The first time, the dealer reset the light during a visit for a brake
> rotor issue, but found no problems. Gas cap OK, both times. Suggestions?
>
> tw
> --
> __________________________________________________ ___________________
> 2003 TJ Rubicon * 2001 XJ Sport * 1971 Bill Stroppe Baja Bronco
>
> "There is a very fine line between 'hobby' and 'mental illness'."
>
> Pronunciation: 'jEp Function: noun Date: 1940
>
> Etymology: from g. p. (G= 'Government' P= '80 inch wheelbase')
> A small general-purpose motor vehicle with 80" wheelbase, 1/4-ton
> capacity and four-wheel drive used by the U.S. army in World War II.
> __________________________________________________ ___________________
twaldron wrote:
> This is the second time this has happened, otherwise the Jeep runs
> great. Once at about 15k miles and this time at about 50k miles, upon
> cold starting, the engine stumbles (of course no gas pedal), runs really
> rough for about 20-30 seconds, then planes out. This triggers the CHECK
> ENGINE light. The vehicle runs fine after that, but the light stays on.
> The first time, the dealer reset the light during a visit for a brake
> rotor issue, but found no problems. Gas cap OK, both times. Suggestions?
>
> tw
> --
> __________________________________________________ ___________________
> 2003 TJ Rubicon * 2001 XJ Sport * 1971 Bill Stroppe Baja Bronco
>
> "There is a very fine line between 'hobby' and 'mental illness'."
>
> Pronunciation: 'jEp Function: noun Date: 1940
>
> Etymology: from g. p. (G= 'Government' P= '80 inch wheelbase')
> A small general-purpose motor vehicle with 80" wheelbase, 1/4-ton
> capacity and four-wheel drive used by the U.S. army in World War II.
> __________________________________________________ ___________________
#24
Guest
Posts: n/a
Re: XJ stumble, check engine light
fault codes are?????
twaldron wrote:
> This is the second time this has happened, otherwise the Jeep runs
> great. Once at about 15k miles and this time at about 50k miles, upon
> cold starting, the engine stumbles (of course no gas pedal), runs really
> rough for about 20-30 seconds, then planes out. This triggers the CHECK
> ENGINE light. The vehicle runs fine after that, but the light stays on.
> The first time, the dealer reset the light during a visit for a brake
> rotor issue, but found no problems. Gas cap OK, both times. Suggestions?
>
> tw
> --
> __________________________________________________ ___________________
> 2003 TJ Rubicon * 2001 XJ Sport * 1971 Bill Stroppe Baja Bronco
>
> "There is a very fine line between 'hobby' and 'mental illness'."
>
> Pronunciation: 'jEp Function: noun Date: 1940
>
> Etymology: from g. p. (G= 'Government' P= '80 inch wheelbase')
> A small general-purpose motor vehicle with 80" wheelbase, 1/4-ton
> capacity and four-wheel drive used by the U.S. army in World War II.
> __________________________________________________ ___________________
twaldron wrote:
> This is the second time this has happened, otherwise the Jeep runs
> great. Once at about 15k miles and this time at about 50k miles, upon
> cold starting, the engine stumbles (of course no gas pedal), runs really
> rough for about 20-30 seconds, then planes out. This triggers the CHECK
> ENGINE light. The vehicle runs fine after that, but the light stays on.
> The first time, the dealer reset the light during a visit for a brake
> rotor issue, but found no problems. Gas cap OK, both times. Suggestions?
>
> tw
> --
> __________________________________________________ ___________________
> 2003 TJ Rubicon * 2001 XJ Sport * 1971 Bill Stroppe Baja Bronco
>
> "There is a very fine line between 'hobby' and 'mental illness'."
>
> Pronunciation: 'jEp Function: noun Date: 1940
>
> Etymology: from g. p. (G= 'Government' P= '80 inch wheelbase')
> A small general-purpose motor vehicle with 80" wheelbase, 1/4-ton
> capacity and four-wheel drive used by the U.S. army in World War II.
> __________________________________________________ ___________________
#25
Guest
Posts: n/a
Re: XJ stumble, check engine light
fault codes are?????
twaldron wrote:
> This is the second time this has happened, otherwise the Jeep runs
> great. Once at about 15k miles and this time at about 50k miles, upon
> cold starting, the engine stumbles (of course no gas pedal), runs really
> rough for about 20-30 seconds, then planes out. This triggers the CHECK
> ENGINE light. The vehicle runs fine after that, but the light stays on.
> The first time, the dealer reset the light during a visit for a brake
> rotor issue, but found no problems. Gas cap OK, both times. Suggestions?
>
> tw
> --
> __________________________________________________ ___________________
> 2003 TJ Rubicon * 2001 XJ Sport * 1971 Bill Stroppe Baja Bronco
>
> "There is a very fine line between 'hobby' and 'mental illness'."
>
> Pronunciation: 'jEp Function: noun Date: 1940
>
> Etymology: from g. p. (G= 'Government' P= '80 inch wheelbase')
> A small general-purpose motor vehicle with 80" wheelbase, 1/4-ton
> capacity and four-wheel drive used by the U.S. army in World War II.
> __________________________________________________ ___________________
twaldron wrote:
> This is the second time this has happened, otherwise the Jeep runs
> great. Once at about 15k miles and this time at about 50k miles, upon
> cold starting, the engine stumbles (of course no gas pedal), runs really
> rough for about 20-30 seconds, then planes out. This triggers the CHECK
> ENGINE light. The vehicle runs fine after that, but the light stays on.
> The first time, the dealer reset the light during a visit for a brake
> rotor issue, but found no problems. Gas cap OK, both times. Suggestions?
>
> tw
> --
> __________________________________________________ ___________________
> 2003 TJ Rubicon * 2001 XJ Sport * 1971 Bill Stroppe Baja Bronco
>
> "There is a very fine line between 'hobby' and 'mental illness'."
>
> Pronunciation: 'jEp Function: noun Date: 1940
>
> Etymology: from g. p. (G= 'Government' P= '80 inch wheelbase')
> A small general-purpose motor vehicle with 80" wheelbase, 1/4-ton
> capacity and four-wheel drive used by the U.S. army in World War II.
> __________________________________________________ ___________________
#26
Guest
Posts: n/a
Re: XJ stumble, check engine light
Or maybe the idle control circuit just wasn't able to respond as quickly as
it should to the unusual needs of a cold engine, hence the stumbling and
check engine light. When one of my vehicles acts a little "cold blooded" in
the morning, I just feed it some throttle. That usually fixes things. I
have triggered the engine light trying to crawl up a trail, at an engine
speed that was really too low, and almost stalling the engine. I don't know
if I would even bother trying to track this down, if it has only happened
twice in 50k miles.
Earle
"JD Adams" <JDAdams@Softcom.Net> wrote in message
news:1144963496.927196.25000@z34g2000cwc.googlegro ups.com...
> > Gas cap OK, both times. Suggestions?
>
> May I venture a guess? I've seen this before and the cause is pretty
> obscure, even to seasoned mechanics.
>
> I am assuming you have the 4.0 with hydraulic lifters.
>
> Sometimes, rarely, a stuck oil pressure relief valve piston will cause
> the valves to hang upon when the engine is started cold, creating a
> loss of compression, which triggers the MIL. Usually, the valve will
> settle back into its normal position and all symptoms dissappear.
> Sometimes for a long time, sometimes for a day.
>
> Usually, you will get a bunch of codes aside from 300 pointing to
> individual cylinders that are misfiring along with the 300, sometimes
> not, depending on how the PCM was programmed.
>
> If this is only happening when the engine is cold, this would be my
> best guess. You could hook up a known-good oil pressure guage to
> verify this. Other symtoms of this include oil filter expansion, oil
> leakage, stalling on initial startup and hard restarting.
>
> You will have to consult with your mechanic about a remedy; I can't
> help you there.
>
> -JD
>
it should to the unusual needs of a cold engine, hence the stumbling and
check engine light. When one of my vehicles acts a little "cold blooded" in
the morning, I just feed it some throttle. That usually fixes things. I
have triggered the engine light trying to crawl up a trail, at an engine
speed that was really too low, and almost stalling the engine. I don't know
if I would even bother trying to track this down, if it has only happened
twice in 50k miles.
Earle
"JD Adams" <JDAdams@Softcom.Net> wrote in message
news:1144963496.927196.25000@z34g2000cwc.googlegro ups.com...
> > Gas cap OK, both times. Suggestions?
>
> May I venture a guess? I've seen this before and the cause is pretty
> obscure, even to seasoned mechanics.
>
> I am assuming you have the 4.0 with hydraulic lifters.
>
> Sometimes, rarely, a stuck oil pressure relief valve piston will cause
> the valves to hang upon when the engine is started cold, creating a
> loss of compression, which triggers the MIL. Usually, the valve will
> settle back into its normal position and all symptoms dissappear.
> Sometimes for a long time, sometimes for a day.
>
> Usually, you will get a bunch of codes aside from 300 pointing to
> individual cylinders that are misfiring along with the 300, sometimes
> not, depending on how the PCM was programmed.
>
> If this is only happening when the engine is cold, this would be my
> best guess. You could hook up a known-good oil pressure guage to
> verify this. Other symtoms of this include oil filter expansion, oil
> leakage, stalling on initial startup and hard restarting.
>
> You will have to consult with your mechanic about a remedy; I can't
> help you there.
>
> -JD
>
#27
Guest
Posts: n/a
Re: XJ stumble, check engine light
Or maybe the idle control circuit just wasn't able to respond as quickly as
it should to the unusual needs of a cold engine, hence the stumbling and
check engine light. When one of my vehicles acts a little "cold blooded" in
the morning, I just feed it some throttle. That usually fixes things. I
have triggered the engine light trying to crawl up a trail, at an engine
speed that was really too low, and almost stalling the engine. I don't know
if I would even bother trying to track this down, if it has only happened
twice in 50k miles.
Earle
"JD Adams" <JDAdams@Softcom.Net> wrote in message
news:1144963496.927196.25000@z34g2000cwc.googlegro ups.com...
> > Gas cap OK, both times. Suggestions?
>
> May I venture a guess? I've seen this before and the cause is pretty
> obscure, even to seasoned mechanics.
>
> I am assuming you have the 4.0 with hydraulic lifters.
>
> Sometimes, rarely, a stuck oil pressure relief valve piston will cause
> the valves to hang upon when the engine is started cold, creating a
> loss of compression, which triggers the MIL. Usually, the valve will
> settle back into its normal position and all symptoms dissappear.
> Sometimes for a long time, sometimes for a day.
>
> Usually, you will get a bunch of codes aside from 300 pointing to
> individual cylinders that are misfiring along with the 300, sometimes
> not, depending on how the PCM was programmed.
>
> If this is only happening when the engine is cold, this would be my
> best guess. You could hook up a known-good oil pressure guage to
> verify this. Other symtoms of this include oil filter expansion, oil
> leakage, stalling on initial startup and hard restarting.
>
> You will have to consult with your mechanic about a remedy; I can't
> help you there.
>
> -JD
>
it should to the unusual needs of a cold engine, hence the stumbling and
check engine light. When one of my vehicles acts a little "cold blooded" in
the morning, I just feed it some throttle. That usually fixes things. I
have triggered the engine light trying to crawl up a trail, at an engine
speed that was really too low, and almost stalling the engine. I don't know
if I would even bother trying to track this down, if it has only happened
twice in 50k miles.
Earle
"JD Adams" <JDAdams@Softcom.Net> wrote in message
news:1144963496.927196.25000@z34g2000cwc.googlegro ups.com...
> > Gas cap OK, both times. Suggestions?
>
> May I venture a guess? I've seen this before and the cause is pretty
> obscure, even to seasoned mechanics.
>
> I am assuming you have the 4.0 with hydraulic lifters.
>
> Sometimes, rarely, a stuck oil pressure relief valve piston will cause
> the valves to hang upon when the engine is started cold, creating a
> loss of compression, which triggers the MIL. Usually, the valve will
> settle back into its normal position and all symptoms dissappear.
> Sometimes for a long time, sometimes for a day.
>
> Usually, you will get a bunch of codes aside from 300 pointing to
> individual cylinders that are misfiring along with the 300, sometimes
> not, depending on how the PCM was programmed.
>
> If this is only happening when the engine is cold, this would be my
> best guess. You could hook up a known-good oil pressure guage to
> verify this. Other symtoms of this include oil filter expansion, oil
> leakage, stalling on initial startup and hard restarting.
>
> You will have to consult with your mechanic about a remedy; I can't
> help you there.
>
> -JD
>
#28
Guest
Posts: n/a
Re: XJ stumble, check engine light
Or maybe the idle control circuit just wasn't able to respond as quickly as
it should to the unusual needs of a cold engine, hence the stumbling and
check engine light. When one of my vehicles acts a little "cold blooded" in
the morning, I just feed it some throttle. That usually fixes things. I
have triggered the engine light trying to crawl up a trail, at an engine
speed that was really too low, and almost stalling the engine. I don't know
if I would even bother trying to track this down, if it has only happened
twice in 50k miles.
Earle
"JD Adams" <JDAdams@Softcom.Net> wrote in message
news:1144963496.927196.25000@z34g2000cwc.googlegro ups.com...
> > Gas cap OK, both times. Suggestions?
>
> May I venture a guess? I've seen this before and the cause is pretty
> obscure, even to seasoned mechanics.
>
> I am assuming you have the 4.0 with hydraulic lifters.
>
> Sometimes, rarely, a stuck oil pressure relief valve piston will cause
> the valves to hang upon when the engine is started cold, creating a
> loss of compression, which triggers the MIL. Usually, the valve will
> settle back into its normal position and all symptoms dissappear.
> Sometimes for a long time, sometimes for a day.
>
> Usually, you will get a bunch of codes aside from 300 pointing to
> individual cylinders that are misfiring along with the 300, sometimes
> not, depending on how the PCM was programmed.
>
> If this is only happening when the engine is cold, this would be my
> best guess. You could hook up a known-good oil pressure guage to
> verify this. Other symtoms of this include oil filter expansion, oil
> leakage, stalling on initial startup and hard restarting.
>
> You will have to consult with your mechanic about a remedy; I can't
> help you there.
>
> -JD
>
it should to the unusual needs of a cold engine, hence the stumbling and
check engine light. When one of my vehicles acts a little "cold blooded" in
the morning, I just feed it some throttle. That usually fixes things. I
have triggered the engine light trying to crawl up a trail, at an engine
speed that was really too low, and almost stalling the engine. I don't know
if I would even bother trying to track this down, if it has only happened
twice in 50k miles.
Earle
"JD Adams" <JDAdams@Softcom.Net> wrote in message
news:1144963496.927196.25000@z34g2000cwc.googlegro ups.com...
> > Gas cap OK, both times. Suggestions?
>
> May I venture a guess? I've seen this before and the cause is pretty
> obscure, even to seasoned mechanics.
>
> I am assuming you have the 4.0 with hydraulic lifters.
>
> Sometimes, rarely, a stuck oil pressure relief valve piston will cause
> the valves to hang upon when the engine is started cold, creating a
> loss of compression, which triggers the MIL. Usually, the valve will
> settle back into its normal position and all symptoms dissappear.
> Sometimes for a long time, sometimes for a day.
>
> Usually, you will get a bunch of codes aside from 300 pointing to
> individual cylinders that are misfiring along with the 300, sometimes
> not, depending on how the PCM was programmed.
>
> If this is only happening when the engine is cold, this would be my
> best guess. You could hook up a known-good oil pressure guage to
> verify this. Other symtoms of this include oil filter expansion, oil
> leakage, stalling on initial startup and hard restarting.
>
> You will have to consult with your mechanic about a remedy; I can't
> help you there.
>
> -JD
>
#29
Guest
Posts: n/a
Re: XJ stumble, check engine light
You aren't one of those people who covers the 'check engine' light with
a piece of black tape, are you?
My Actron OBD scanner paid for itself the first time I used it. Just
used it to run a pre-emissions inspection check, and it caught a small
item that would have failed me. C'mon now...be a big boy...go buy one.
If it makes you feel any better, you can use it on any late-model
vehicle. Your neighbors might even want to slip you a 20 to borrow it
now and then.
a piece of black tape, are you?
My Actron OBD scanner paid for itself the first time I used it. Just
used it to run a pre-emissions inspection check, and it caught a small
item that would have failed me. C'mon now...be a big boy...go buy one.
If it makes you feel any better, you can use it on any late-model
vehicle. Your neighbors might even want to slip you a 20 to borrow it
now and then.
#30
Guest
Posts: n/a
Re: XJ stumble, check engine light
You aren't one of those people who covers the 'check engine' light with
a piece of black tape, are you?
My Actron OBD scanner paid for itself the first time I used it. Just
used it to run a pre-emissions inspection check, and it caught a small
item that would have failed me. C'mon now...be a big boy...go buy one.
If it makes you feel any better, you can use it on any late-model
vehicle. Your neighbors might even want to slip you a 20 to borrow it
now and then.
a piece of black tape, are you?
My Actron OBD scanner paid for itself the first time I used it. Just
used it to run a pre-emissions inspection check, and it caught a small
item that would have failed me. C'mon now...be a big boy...go buy one.
If it makes you feel any better, you can use it on any late-model
vehicle. Your neighbors might even want to slip you a 20 to borrow it
now and then.