Hey y'all;

I've got one of those "mystery problems," could use some help. I drive
98 Cherokee Sport, 4.0L inline 6, with manual transmission, around 110K
miles. The problem I have is this: at about 2000 RPM, the engine
loses power and sometimes misses. During the latter incidents, it acts
as though its not getting enough fuel, something like the beginnings of
a fuel pump dying but not as severe. The problem is more pronounced if
under load (AC on, carrying heavy stuff, going uphill..) or in higher
gear ranges, and seems to be worse when the outside air temperature
changes rapidly. Gas mileage has dropped by about 5-6 mpg since the
problem started.

So far, several visits to the dealership have been fruitless. There are
no codes being generated, so there's not much to go on. The oxygen
sensor was replaced a few months before the current issue started due
to a different problem, and the throttle body & connections thoroughly
cleaned then, too. The dealership tried to tell me I had "weak valve
springs" and needed a complete engine overhaul ($800+) to replace them,
which did not sound right to me at all. I've had a lot of trouble
finding a good garage nearby, so I'm ready to start tinkering myself in
what little spare time I have. :-(

I've seen a lot of stuff on here about bad TPS sensors and/or bad
connections, could this be the cause of my problem, too? I don't have
a big toolkit nor am I terribly knowledgeable about fuel systems or
testing voltages and such, so I'm not sure how best for me to start
working with this. I bought a Haynes Manual a long time ago, but it
doesn't have much info in it about sensors & such for the 1998 model (&
newer).

Also, just recently, it has started with a new problem: when I turn on
the left turn signal, both lights blink as though I'd turned on the
hazards. Doesn't happen with the right blinker, doesn't happen if the
ignition is off and the car parked, only when running & in motion.
Almost simultaneously, the rear passenger electric door lock mechanism
began malfunctioning, and refusing to lock or unlock while making a
nasty grinding noise. I have no idea if these problems could be related
in any way (grounds gone bad? shorts? lightning? ) but I just wanted to
mention them in case they are clues.

Thanks for whatever help you can offer.

 

I'm going to believe your Stealership, and confirm weak valve
springs act the way describe. And they have the equipment that tests for
that, and so does your Cherokee's Onboard Diagnostics:
http://www.wjjeeps.com/faultcodes.htm There are mechanics that will
replace them without pulling the head to cut the labor in half.
God Bless America, Bill O|||||||O
mailto:-------------------- http://www.----------.com/

katuah wrote:
>
> Hey y'all;
>
> I've got one of those "mystery problems," could use some help. I drive
> 98 Cherokee Sport, 4.0L inline 6, with manual transmission, around 110K
> miles. The problem I have is this: at about 2000 RPM, the engine
> loses power and sometimes misses. During the latter incidents, it acts
> as though its not getting enough fuel, something like the beginnings of
> a fuel pump dying but not as severe. The problem is more pronounced if
> under load (AC on, carrying heavy stuff, going uphill..) or in higher
> gear ranges, and seems to be worse when the outside air temperature
> changes rapidly. Gas mileage has dropped by about 5-6 mpg since the
> problem started.
>
> So far, several visits to the dealership have been fruitless. There are
> no codes being generated, so there's not much to go on. The oxygen
> sensor was replaced a few months before the current issue started due
> to a different problem, and the throttle body & connections thoroughly
> cleaned then, too. The dealership tried to tell me I had "weak valve
> springs" and needed a complete engine overhaul ($800+) to replace them,
> which did not sound right to me at all. I've had a lot of trouble
> finding a good garage nearby, so I'm ready to start tinkering myself in
> what little spare time I have. :-(
>
> I've seen a lot of stuff on here about bad TPS sensors and/or bad
> connections, could this be the cause of my problem, too? I don't have
> a big toolkit nor am I terribly knowledgeable about fuel systems or
> testing voltages and such, so I'm not sure how best for me to start
> working with this. I bought a Haynes Manual a long time ago, but it
> doesn't have much info in it about sensors & such for the 1998 model (&
> newer).
>
> Also, just recently, it has started with a new problem: when I turn on
> the left turn signal, both lights blink as though I'd turned on the
> hazards. Doesn't happen with the right blinker, doesn't happen if the
> ignition is off and the car parked, only when running & in motion.
> Almost simultaneously, the rear passenger electric door lock mechanism
> began malfunctioning, and refusing to lock or unlock while making a
> nasty grinding noise. I have no idea if these problems could be related
> in any way (grounds gone bad? shorts? lightning? ) but I just wanted to
> mention them in case they are clues.
>
> Thanks for whatever help you can offer.

 

I'm going to believe your Stealership, and confirm weak valve
springs act the way describe. And they have the equipment that tests for
that, and so does your Cherokee's Onboard Diagnostics:
http://www.wjjeeps.com/faultcodes.htm There are mechanics that will
replace them without pulling the head to cut the labor in half.
God Bless America, Bill O|||||||O
mailto:-------------------- http://www.----------.com/

katuah wrote:
>
> Hey y'all;
>
> I've got one of those "mystery problems," could use some help. I drive
> 98 Cherokee Sport, 4.0L inline 6, with manual transmission, around 110K
> miles. The problem I have is this: at about 2000 RPM, the engine
> loses power and sometimes misses. During the latter incidents, it acts
> as though its not getting enough fuel, something like the beginnings of
> a fuel pump dying but not as severe. The problem is more pronounced if
> under load (AC on, carrying heavy stuff, going uphill..) or in higher
> gear ranges, and seems to be worse when the outside air temperature
> changes rapidly. Gas mileage has dropped by about 5-6 mpg since the
> problem started.
>
> So far, several visits to the dealership have been fruitless. There are
> no codes being generated, so there's not much to go on. The oxygen
> sensor was replaced a few months before the current issue started due
> to a different problem, and the throttle body & connections thoroughly
> cleaned then, too. The dealership tried to tell me I had "weak valve
> springs" and needed a complete engine overhaul ($800+) to replace them,
> which did not sound right to me at all. I've had a lot of trouble
> finding a good garage nearby, so I'm ready to start tinkering myself in
> what little spare time I have. :-(
>
> I've seen a lot of stuff on here about bad TPS sensors and/or bad
> connections, could this be the cause of my problem, too? I don't have
> a big toolkit nor am I terribly knowledgeable about fuel systems or
> testing voltages and such, so I'm not sure how best for me to start
> working with this. I bought a Haynes Manual a long time ago, but it
> doesn't have much info in it about sensors & such for the 1998 model (&
> newer).
>
> Also, just recently, it has started with a new problem: when I turn on
> the left turn signal, both lights blink as though I'd turned on the
> hazards. Doesn't happen with the right blinker, doesn't happen if the
> ignition is off and the car parked, only when running & in motion.
> Almost simultaneously, the rear passenger electric door lock mechanism
> began malfunctioning, and refusing to lock or unlock while making a
> nasty grinding noise. I have no idea if these problems could be related
> in any way (grounds gone bad? shorts? lightning? ) but I just wanted to
> mention them in case they are clues.
>
> Thanks for whatever help you can offer.

 

I'm going to believe your Stealership, and confirm weak valve
springs act the way describe. And they have the equipment that tests for
that, and so does your Cherokee's Onboard Diagnostics:
http://www.wjjeeps.com/faultcodes.htm There are mechanics that will
replace them without pulling the head to cut the labor in half.
God Bless America, Bill O|||||||O
mailto:-------------------- http://www.----------.com/

katuah wrote:
>
> Hey y'all;
>
> I've got one of those "mystery problems," could use some help. I drive
> 98 Cherokee Sport, 4.0L inline 6, with manual transmission, around 110K
> miles. The problem I have is this: at about 2000 RPM, the engine
> loses power and sometimes misses. During the latter incidents, it acts
> as though its not getting enough fuel, something like the beginnings of
> a fuel pump dying but not as severe. The problem is more pronounced if
> under load (AC on, carrying heavy stuff, going uphill..) or in higher
> gear ranges, and seems to be worse when the outside air temperature
> changes rapidly. Gas mileage has dropped by about 5-6 mpg since the
> problem started.
>
> So far, several visits to the dealership have been fruitless. There are
> no codes being generated, so there's not much to go on. The oxygen
> sensor was replaced a few months before the current issue started due
> to a different problem, and the throttle body & connections thoroughly
> cleaned then, too. The dealership tried to tell me I had "weak valve
> springs" and needed a complete engine overhaul ($800+) to replace them,
> which did not sound right to me at all. I've had a lot of trouble
> finding a good garage nearby, so I'm ready to start tinkering myself in
> what little spare time I have. :-(
>
> I've seen a lot of stuff on here about bad TPS sensors and/or bad
> connections, could this be the cause of my problem, too? I don't have
> a big toolkit nor am I terribly knowledgeable about fuel systems or
> testing voltages and such, so I'm not sure how best for me to start
> working with this. I bought a Haynes Manual a long time ago, but it
> doesn't have much info in it about sensors & such for the 1998 model (&
> newer).
>
> Also, just recently, it has started with a new problem: when I turn on
> the left turn signal, both lights blink as though I'd turned on the
> hazards. Doesn't happen with the right blinker, doesn't happen if the
> ignition is off and the car parked, only when running & in motion.
> Almost simultaneously, the rear passenger electric door lock mechanism
> began malfunctioning, and refusing to lock or unlock while making a
> nasty grinding noise. I have no idea if these problems could be related
> in any way (grounds gone bad? shorts? lightning? ) but I just wanted to
> mention them in case they are clues.
>
> Thanks for whatever help you can offer.

 

I'm going to believe your Stealership, and confirm weak valve
springs act the way describe. And they have the equipment that tests for
that, and so does your Cherokee's Onboard Diagnostics:
http://www.wjjeeps.com/faultcodes.htm There are mechanics that will
replace them without pulling the head to cut the labor in half.
God Bless America, Bill O|||||||O
mailto:-------------------- http://www.----------.com/

katuah wrote:
>
> Hey y'all;
>
> I've got one of those "mystery problems," could use some help. I drive
> 98 Cherokee Sport, 4.0L inline 6, with manual transmission, around 110K
> miles. The problem I have is this: at about 2000 RPM, the engine
> loses power and sometimes misses. During the latter incidents, it acts
> as though its not getting enough fuel, something like the beginnings of
> a fuel pump dying but not as severe. The problem is more pronounced if
> under load (AC on, carrying heavy stuff, going uphill..) or in higher
> gear ranges, and seems to be worse when the outside air temperature
> changes rapidly. Gas mileage has dropped by about 5-6 mpg since the
> problem started.
>
> So far, several visits to the dealership have been fruitless. There are
> no codes being generated, so there's not much to go on. The oxygen
> sensor was replaced a few months before the current issue started due
> to a different problem, and the throttle body & connections thoroughly
> cleaned then, too. The dealership tried to tell me I had "weak valve
> springs" and needed a complete engine overhaul ($800+) to replace them,
> which did not sound right to me at all. I've had a lot of trouble
> finding a good garage nearby, so I'm ready to start tinkering myself in
> what little spare time I have. :-(
>
> I've seen a lot of stuff on here about bad TPS sensors and/or bad
> connections, could this be the cause of my problem, too? I don't have
> a big toolkit nor am I terribly knowledgeable about fuel systems or
> testing voltages and such, so I'm not sure how best for me to start
> working with this. I bought a Haynes Manual a long time ago, but it
> doesn't have much info in it about sensors & such for the 1998 model (&
> newer).
>
> Also, just recently, it has started with a new problem: when I turn on
> the left turn signal, both lights blink as though I'd turned on the
> hazards. Doesn't happen with the right blinker, doesn't happen if the
> ignition is off and the car parked, only when running & in motion.
> Almost simultaneously, the rear passenger electric door lock mechanism
> began malfunctioning, and refusing to lock or unlock while making a
> nasty grinding noise. I have no idea if these problems could be related
> in any way (grounds gone bad? shorts? lightning? ) but I just wanted to
> mention them in case they are clues.
>
> Thanks for whatever help you can offer.

 

Someone else on this group had one of the engines with the bad valve
springs. Jerry B I think....

There are some engines out there with the bad springs, that's for sure.

Mike
86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00
88 Cherokee 235 BFG AT's
Canadian Off Road Trips Photos: Non members can still view!
Jan/06 http://www.imagestation.com/album/pi...?id=2115147590
(More Off Road album links at bottom of the view page)

katuah wrote:
>
> Hey y'all;
>
> I've got one of those "mystery problems," could use some help. I drive
> 98 Cherokee Sport, 4.0L inline 6, with manual transmission, around 110K
> miles. The problem I have is this: at about 2000 RPM, the engine
> loses power and sometimes misses. During the latter incidents, it acts
> as though its not getting enough fuel, something like the beginnings of
> a fuel pump dying but not as severe. The problem is more pronounced if
> under load (AC on, carrying heavy stuff, going uphill..) or in higher
> gear ranges, and seems to be worse when the outside air temperature
> changes rapidly. Gas mileage has dropped by about 5-6 mpg since the
> problem started.
>
> So far, several visits to the dealership have been fruitless. There are
> no codes being generated, so there's not much to go on. The oxygen
> sensor was replaced a few months before the current issue started due
> to a different problem, and the throttle body & connections thoroughly
> cleaned then, too. The dealership tried to tell me I had "weak valve
> springs" and needed a complete engine overhaul ($800+) to replace them,
> which did not sound right to me at all. I've had a lot of trouble
> finding a good garage nearby, so I'm ready to start tinkering myself in
> what little spare time I have. :-(
>
> I've seen a lot of stuff on here about bad TPS sensors and/or bad
> connections, could this be the cause of my problem, too? I don't have
> a big toolkit nor am I terribly knowledgeable about fuel systems or
> testing voltages and such, so I'm not sure how best for me to start
> working with this. I bought a Haynes Manual a long time ago, but it
> doesn't have much info in it about sensors & such for the 1998 model (&
> newer).
>
> Also, just recently, it has started with a new problem: when I turn on
> the left turn signal, both lights blink as though I'd turned on the
> hazards. Doesn't happen with the right blinker, doesn't happen if the
> ignition is off and the car parked, only when running & in motion.
> Almost simultaneously, the rear passenger electric door lock mechanism
> began malfunctioning, and refusing to lock or unlock while making a
> nasty grinding noise. I have no idea if these problems could be related
> in any way (grounds gone bad? shorts? lightning? ) but I just wanted to
> mention them in case they are clues.
>
> Thanks for whatever help you can offer.

 

Someone else on this group had one of the engines with the bad valve
springs. Jerry B I think....

There are some engines out there with the bad springs, that's for sure.

Mike
86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00
88 Cherokee 235 BFG AT's
Canadian Off Road Trips Photos: Non members can still view!
Jan/06 http://www.imagestation.com/album/pi...?id=2115147590
(More Off Road album links at bottom of the view page)

katuah wrote:
>
> Hey y'all;
>
> I've got one of those "mystery problems," could use some help. I drive
> 98 Cherokee Sport, 4.0L inline 6, with manual transmission, around 110K
> miles. The problem I have is this: at about 2000 RPM, the engine
> loses power and sometimes misses. During the latter incidents, it acts
> as though its not getting enough fuel, something like the beginnings of
> a fuel pump dying but not as severe. The problem is more pronounced if
> under load (AC on, carrying heavy stuff, going uphill..) or in higher
> gear ranges, and seems to be worse when the outside air temperature
> changes rapidly. Gas mileage has dropped by about 5-6 mpg since the
> problem started.
>
> So far, several visits to the dealership have been fruitless. There are
> no codes being generated, so there's not much to go on. The oxygen
> sensor was replaced a few months before the current issue started due
> to a different problem, and the throttle body & connections thoroughly
> cleaned then, too. The dealership tried to tell me I had "weak valve
> springs" and needed a complete engine overhaul ($800+) to replace them,
> which did not sound right to me at all. I've had a lot of trouble
> finding a good garage nearby, so I'm ready to start tinkering myself in
> what little spare time I have. :-(
>
> I've seen a lot of stuff on here about bad TPS sensors and/or bad
> connections, could this be the cause of my problem, too? I don't have
> a big toolkit nor am I terribly knowledgeable about fuel systems or
> testing voltages and such, so I'm not sure how best for me to start
> working with this. I bought a Haynes Manual a long time ago, but it
> doesn't have much info in it about sensors & such for the 1998 model (&
> newer).
>
> Also, just recently, it has started with a new problem: when I turn on
> the left turn signal, both lights blink as though I'd turned on the
> hazards. Doesn't happen with the right blinker, doesn't happen if the
> ignition is off and the car parked, only when running & in motion.
> Almost simultaneously, the rear passenger electric door lock mechanism
> began malfunctioning, and refusing to lock or unlock while making a
> nasty grinding noise. I have no idea if these problems could be related
> in any way (grounds gone bad? shorts? lightning? ) but I just wanted to
> mention them in case they are clues.
>
> Thanks for whatever help you can offer.

 

Someone else on this group had one of the engines with the bad valve
springs. Jerry B I think....

There are some engines out there with the bad springs, that's for sure.

Mike
86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00
88 Cherokee 235 BFG AT's
Canadian Off Road Trips Photos: Non members can still view!
Jan/06 http://www.imagestation.com/album/pi...?id=2115147590
(More Off Road album links at bottom of the view page)

katuah wrote:
>
> Hey y'all;
>
> I've got one of those "mystery problems," could use some help. I drive
> 98 Cherokee Sport, 4.0L inline 6, with manual transmission, around 110K
> miles. The problem I have is this: at about 2000 RPM, the engine
> loses power and sometimes misses. During the latter incidents, it acts
> as though its not getting enough fuel, something like the beginnings of
> a fuel pump dying but not as severe. The problem is more pronounced if
> under load (AC on, carrying heavy stuff, going uphill..) or in higher
> gear ranges, and seems to be worse when the outside air temperature
> changes rapidly. Gas mileage has dropped by about 5-6 mpg since the
> problem started.
>
> So far, several visits to the dealership have been fruitless. There are
> no codes being generated, so there's not much to go on. The oxygen
> sensor was replaced a few months before the current issue started due
> to a different problem, and the throttle body & connections thoroughly
> cleaned then, too. The dealership tried to tell me I had "weak valve
> springs" and needed a complete engine overhaul ($800+) to replace them,
> which did not sound right to me at all. I've had a lot of trouble
> finding a good garage nearby, so I'm ready to start tinkering myself in
> what little spare time I have. :-(
>
> I've seen a lot of stuff on here about bad TPS sensors and/or bad
> connections, could this be the cause of my problem, too? I don't have
> a big toolkit nor am I terribly knowledgeable about fuel systems or
> testing voltages and such, so I'm not sure how best for me to start
> working with this. I bought a Haynes Manual a long time ago, but it
> doesn't have much info in it about sensors & such for the 1998 model (&
> newer).
>
> Also, just recently, it has started with a new problem: when I turn on
> the left turn signal, both lights blink as though I'd turned on the
> hazards. Doesn't happen with the right blinker, doesn't happen if the
> ignition is off and the car parked, only when running & in motion.
> Almost simultaneously, the rear passenger electric door lock mechanism
> began malfunctioning, and refusing to lock or unlock while making a
> nasty grinding noise. I have no idea if these problems could be related
> in any way (grounds gone bad? shorts? lightning? ) but I just wanted to
> mention them in case they are clues.
>
> Thanks for whatever help you can offer.

 

Someone else on this group had one of the engines with the bad valve
springs. Jerry B I think....

There are some engines out there with the bad springs, that's for sure.

Mike
86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00
88 Cherokee 235 BFG AT's
Canadian Off Road Trips Photos: Non members can still view!
Jan/06 http://www.imagestation.com/album/pi...?id=2115147590
(More Off Road album links at bottom of the view page)

katuah wrote:
>
> Hey y'all;
>
> I've got one of those "mystery problems," could use some help. I drive
> 98 Cherokee Sport, 4.0L inline 6, with manual transmission, around 110K
> miles. The problem I have is this: at about 2000 RPM, the engine
> loses power and sometimes misses. During the latter incidents, it acts
> as though its not getting enough fuel, something like the beginnings of
> a fuel pump dying but not as severe. The problem is more pronounced if
> under load (AC on, carrying heavy stuff, going uphill..) or in higher
> gear ranges, and seems to be worse when the outside air temperature
> changes rapidly. Gas mileage has dropped by about 5-6 mpg since the
> problem started.
>
> So far, several visits to the dealership have been fruitless. There are
> no codes being generated, so there's not much to go on. The oxygen
> sensor was replaced a few months before the current issue started due
> to a different problem, and the throttle body & connections thoroughly
> cleaned then, too. The dealership tried to tell me I had "weak valve
> springs" and needed a complete engine overhaul ($800+) to replace them,
> which did not sound right to me at all. I've had a lot of trouble
> finding a good garage nearby, so I'm ready to start tinkering myself in
> what little spare time I have. :-(
>
> I've seen a lot of stuff on here about bad TPS sensors and/or bad
> connections, could this be the cause of my problem, too? I don't have
> a big toolkit nor am I terribly knowledgeable about fuel systems or
> testing voltages and such, so I'm not sure how best for me to start
> working with this. I bought a Haynes Manual a long time ago, but it
> doesn't have much info in it about sensors & such for the 1998 model (&
> newer).
>
> Also, just recently, it has started with a new problem: when I turn on
> the left turn signal, both lights blink as though I'd turned on the
> hazards. Doesn't happen with the right blinker, doesn't happen if the
> ignition is off and the car parked, only when running & in motion.
> Almost simultaneously, the rear passenger electric door lock mechanism
> began malfunctioning, and refusing to lock or unlock while making a
> nasty grinding noise. I have no idea if these problems could be related
> in any way (grounds gone bad? shorts? lightning? ) but I just wanted to
> mention them in case they are clues.
>
> Thanks for whatever help you can offer.

 

True.
God Bless America, Bill O|||||||O
mailto:-------------------- http://www.----------.com/

Mike Romain wrote:
>
> Someone else on this group had one of the engines with the bad valve
> springs. Jerry B I think....
>
> There are some engines out there with the bad springs, that's for sure.
>
> Mike
> 86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00
> 88 Cherokee 235 BFG AT's
> Canadian Off Road Trips Photos: Non members can still view!
> Jan/06 http://www.imagestation.com/album/pi...?id=2115147590
> (More Off Road album links at bottom of the view page)