Engine has been running rough in my 98 TJ, 6-cyl. When coming to a stop
and taking it out of gear (auto tranny) the idle speed would jump up
sometimes to abouv 1000 RMP. I'd have to quick step on the gas to get
it to come back down- almost as if it were stuck. But the engine seemed
to be missing also. My old 86 XJ did this and turned out to be a bad
vacuum line to the egr valve. Same symptoms here but can't seem to find
the egr valve on the TJ. Put in new plugs, wires, cap/roter, and
ignition coil. Engine still jerks at all speeds. Got sucked in to
buying the split fire plugs. After attmpting to adjust the gap to .035
I noticed on the packaging that the plugs were "factory set" and no gap
adjustment is required. Could I have screwed them up? Any chance it
could be something else- egr, pcv, O2 sensor?

 

Cleaned your throttle body recently?

http://www.off-road.com/jeep/cheroke...gine/tbody.htm
http://www.revbeergoggles.com/tb/tb.html

Steve
http://xjeep.dyndns.org

gkucera wrote:
> Engine has been running rough in my 98 TJ, 6-cyl. When coming to a stop
> and taking it out of gear (auto tranny) the idle speed would jump up
> sometimes to abouv 1000 RMP. I'd have to quick step on the gas to get
> it to come back down- almost as if it were stuck. But the engine seemed
> to be missing also. My old 86 XJ did this and turned out to be a bad
> vacuum line to the egr valve. Same symptoms here but can't seem to find
> the egr valve on the TJ. Put in new plugs, wires, cap/roter, and
> ignition coil. Engine still jerks at all speeds. Got sucked in to
> buying the split fire plugs. After attmpting to adjust the gap to .035
> I noticed on the packaging that the plugs were "factory set" and no gap
> adjustment is required. Could I have screwed them up? Any chance it
> could be something else- egr, pcv, O2 sensor?

 

Cleaned your throttle body recently?

http://www.off-road.com/jeep/cheroke...gine/tbody.htm
http://www.revbeergoggles.com/tb/tb.html

Steve
http://xjeep.dyndns.org

gkucera wrote:
> Engine has been running rough in my 98 TJ, 6-cyl. When coming to a stop
> and taking it out of gear (auto tranny) the idle speed would jump up
> sometimes to abouv 1000 RMP. I'd have to quick step on the gas to get
> it to come back down- almost as if it were stuck. But the engine seemed
> to be missing also. My old 86 XJ did this and turned out to be a bad
> vacuum line to the egr valve. Same symptoms here but can't seem to find
> the egr valve on the TJ. Put in new plugs, wires, cap/roter, and
> ignition coil. Engine still jerks at all speeds. Got sucked in to
> buying the split fire plugs. After attmpting to adjust the gap to .035
> I noticed on the packaging that the plugs were "factory set" and no gap
> adjustment is required. Could I have screwed them up? Any chance it
> could be something else- egr, pcv, O2 sensor?

 

Cleaned your throttle body recently?

http://www.off-road.com/jeep/cheroke...gine/tbody.htm
http://www.revbeergoggles.com/tb/tb.html

Steve
http://xjeep.dyndns.org

gkucera wrote:
> Engine has been running rough in my 98 TJ, 6-cyl. When coming to a stop
> and taking it out of gear (auto tranny) the idle speed would jump up
> sometimes to abouv 1000 RMP. I'd have to quick step on the gas to get
> it to come back down- almost as if it were stuck. But the engine seemed
> to be missing also. My old 86 XJ did this and turned out to be a bad
> vacuum line to the egr valve. Same symptoms here but can't seem to find
> the egr valve on the TJ. Put in new plugs, wires, cap/roter, and
> ignition coil. Engine still jerks at all speeds. Got sucked in to
> buying the split fire plugs. After attmpting to adjust the gap to .035
> I noticed on the packaging that the plugs were "factory set" and no gap
> adjustment is required. Could I have screwed them up? Any chance it
> could be something else- egr, pcv, O2 sensor?

 

Cleaned your throttle body recently?

http://www.off-road.com/jeep/cheroke...gine/tbody.htm
http://www.revbeergoggles.com/tb/tb.html

Steve
http://xjeep.dyndns.org

gkucera wrote:
> Engine has been running rough in my 98 TJ, 6-cyl. When coming to a stop
> and taking it out of gear (auto tranny) the idle speed would jump up
> sometimes to abouv 1000 RMP. I'd have to quick step on the gas to get
> it to come back down- almost as if it were stuck. But the engine seemed
> to be missing also. My old 86 XJ did this and turned out to be a bad
> vacuum line to the egr valve. Same symptoms here but can't seem to find
> the egr valve on the TJ. Put in new plugs, wires, cap/roter, and
> ignition coil. Engine still jerks at all speeds. Got sucked in to
> buying the split fire plugs. After attmpting to adjust the gap to .035
> I noticed on the packaging that the plugs were "factory set" and no gap
> adjustment is required. Could I have screwed them up? Any chance it
> could be something else- egr, pcv, O2 sensor?

 

check your throttle position sensor




"Steve" <steve@xjeep.dyndns.org> wrote in message
news:Q0BVe.89642$Ph4.2846516@ursa-nb00s0.nbnet.nb.ca...
> Cleaned your throttle body recently?
>
> http://www.off-road.com/jeep/cheroke...gine/tbody.htm
> http://www.revbeergoggles.com/tb/tb.html
>
> Steve
> http://xjeep.dyndns.org
>
> gkucera wrote:
> > Engine has been running rough in my 98 TJ, 6-cyl. When coming to a stop
> > and taking it out of gear (auto tranny) the idle speed would jump up
> > sometimes to abouv 1000 RMP. I'd have to quick step on the gas to get
> > it to come back down- almost as if it were stuck. But the engine seemed
> > to be missing also. My old 86 XJ did this and turned out to be a bad
> > vacuum line to the egr valve. Same symptoms here but can't seem to find
> > the egr valve on the TJ. Put in new plugs, wires, cap/roter, and
> > ignition coil. Engine still jerks at all speeds. Got sucked in to
> > buying the split fire plugs. After attmpting to adjust the gap to .035
> > I noticed on the packaging that the plugs were "factory set" and no gap
> > adjustment is required. Could I have screwed them up? Any chance it
> > could be something else- egr, pcv, O2 sensor?

 

check your throttle position sensor




"Steve" <steve@xjeep.dyndns.org> wrote in message
news:Q0BVe.89642$Ph4.2846516@ursa-nb00s0.nbnet.nb.ca...
> Cleaned your throttle body recently?
>
> http://www.off-road.com/jeep/cheroke...gine/tbody.htm
> http://www.revbeergoggles.com/tb/tb.html
>
> Steve
> http://xjeep.dyndns.org
>
> gkucera wrote:
> > Engine has been running rough in my 98 TJ, 6-cyl. When coming to a stop
> > and taking it out of gear (auto tranny) the idle speed would jump up
> > sometimes to abouv 1000 RMP. I'd have to quick step on the gas to get
> > it to come back down- almost as if it were stuck. But the engine seemed
> > to be missing also. My old 86 XJ did this and turned out to be a bad
> > vacuum line to the egr valve. Same symptoms here but can't seem to find
> > the egr valve on the TJ. Put in new plugs, wires, cap/roter, and
> > ignition coil. Engine still jerks at all speeds. Got sucked in to
> > buying the split fire plugs. After attmpting to adjust the gap to .035
> > I noticed on the packaging that the plugs were "factory set" and no gap
> > adjustment is required. Could I have screwed them up? Any chance it
> > could be something else- egr, pcv, O2 sensor?

 

check your throttle position sensor




"Steve" <steve@xjeep.dyndns.org> wrote in message
news:Q0BVe.89642$Ph4.2846516@ursa-nb00s0.nbnet.nb.ca...
> Cleaned your throttle body recently?
>
> http://www.off-road.com/jeep/cheroke...gine/tbody.htm
> http://www.revbeergoggles.com/tb/tb.html
>
> Steve
> http://xjeep.dyndns.org
>
> gkucera wrote:
> > Engine has been running rough in my 98 TJ, 6-cyl. When coming to a stop
> > and taking it out of gear (auto tranny) the idle speed would jump up
> > sometimes to abouv 1000 RMP. I'd have to quick step on the gas to get
> > it to come back down- almost as if it were stuck. But the engine seemed
> > to be missing also. My old 86 XJ did this and turned out to be a bad
> > vacuum line to the egr valve. Same symptoms here but can't seem to find
> > the egr valve on the TJ. Put in new plugs, wires, cap/roter, and
> > ignition coil. Engine still jerks at all speeds. Got sucked in to
> > buying the split fire plugs. After attmpting to adjust the gap to .035
> > I noticed on the packaging that the plugs were "factory set" and no gap
> > adjustment is required. Could I have screwed them up? Any chance it
> > could be something else- egr, pcv, O2 sensor?

 

check your throttle position sensor




"Steve" <steve@xjeep.dyndns.org> wrote in message
news:Q0BVe.89642$Ph4.2846516@ursa-nb00s0.nbnet.nb.ca...
> Cleaned your throttle body recently?
>
> http://www.off-road.com/jeep/cheroke...gine/tbody.htm
> http://www.revbeergoggles.com/tb/tb.html
>
> Steve
> http://xjeep.dyndns.org
>
> gkucera wrote:
> > Engine has been running rough in my 98 TJ, 6-cyl. When coming to a stop
> > and taking it out of gear (auto tranny) the idle speed would jump up
> > sometimes to abouv 1000 RMP. I'd have to quick step on the gas to get
> > it to come back down- almost as if it were stuck. But the engine seemed
> > to be missing also. My old 86 XJ did this and turned out to be a bad
> > vacuum line to the egr valve. Same symptoms here but can't seem to find
> > the egr valve on the TJ. Put in new plugs, wires, cap/roter, and
> > ignition coil. Engine still jerks at all speeds. Got sucked in to
> > buying the split fire plugs. After attmpting to adjust the gap to .035
> > I noticed on the packaging that the plugs were "factory set" and no gap
> > adjustment is required. Could I have screwed them up? Any chance it
> > could be something else- egr, pcv, O2 sensor?

 

I know this doesn't help you now but...for the cost of those new plugs you
could have had it diagnosed properly. Have you tried getting the codes off
the odometer? (not sure if that's available on a 98)
-Brian

"gkucera" <gkucera@yahoo.com> wrote in message
news:D%xVe.545$7E5.378@bignews1.bellsouth.net...
> Engine has been running rough in my 98 TJ, 6-cyl. When coming to a stop
> and taking it out of gear (auto tranny) the idle speed would jump up
> sometimes to abouv 1000 RMP. I'd have to quick step on the gas to get it
> to come back down- almost as if it were stuck. But the engine seemed to
> be missing also. My old 86 XJ did this and turned out to be a bad vacuum
> line to the egr valve. Same symptoms here but can't seem to find the egr
> valve on the TJ. Put in new plugs, wires, cap/roter, and ignition coil.
> Engine still jerks at all speeds. Got sucked in to buying the split fire
> plugs. After attmpting to adjust the gap to .035 I noticed on the
> packaging that the plugs were "factory set" and no gap adjustment is
> required. Could I have screwed them up? Any chance it could be something
> else- egr, pcv, O2 sensor?