jeepnfonz

So I have on engine code on my 2001 tj sport with the 4.0 in line six.
the code is 0301 which I believe is misfire on cylinder one. which
makes sense it back fires run like crap and no power. I replaced the
spark plugs(easy and cheap fix). that solved the problem till I got
after it and it started up again same code same symtoms does anyone
have any clue what my next step would be what would be causing this. I
don't really understand thenew system with no cap or rotor or wires
please help......

billy ray

Okay.... You have 3 coil packs on a rail and are getting only one code you
can assume that it is not an electrical or coil problem as cylinder 1 and 6
fire off the same coil pack.

Did you blank the code with a tool or by disconnecting the battery?

Did you save the old plug?

What did it look like?

Was it unusually clean compared to the others?

Was it carboned or oily?

What does the exhaust look and smell like?

Is this a recent or existing problem?

Did it happen all at once?

What, if anything, did you do when or shortly before the problem started?

How many miles?

What kind are the new plugs?

Have you cleaned the throttle body?

Did you use an upper engine/ valve carbon cleaner (SeaFoam, etc?)



"jeepnfonz" <jeepnfonz@netscape.net> wrote in message
news:1155024110.444501.9630@m73g2000cwd.googlegrou ps.com...
> So I have on engine code on my 2001 tj sport with the 4.0 in line six.
> the code is 0301 which I believe is misfire on cylinder one. which
> makes sense it back fires run like crap and no power. I replaced the
> spark plugs(easy and cheap fix). that solved the problem till I got
> after it and it started up again same code same symtoms does anyone
> have any clue what my next step would be what would be causing this. I
> don't really understand thenew system with no cap or rotor or wires
> please help......
>

billy ray

Okay.... You have 3 coil packs on a rail and are getting only one code you
can assume that it is not an electrical or coil problem as cylinder 1 and 6
fire off the same coil pack.

Did you blank the code with a tool or by disconnecting the battery?

Did you save the old plug?

What did it look like?

Was it unusually clean compared to the others?

Was it carboned or oily?

What does the exhaust look and smell like?

Is this a recent or existing problem?

Did it happen all at once?

What, if anything, did you do when or shortly before the problem started?

How many miles?

What kind are the new plugs?

Have you cleaned the throttle body?

Did you use an upper engine/ valve carbon cleaner (SeaFoam, etc?)



"jeepnfonz" <jeepnfonz@netscape.net> wrote in message
news:1155024110.444501.9630@m73g2000cwd.googlegrou ps.com...
> So I have on engine code on my 2001 tj sport with the 4.0 in line six.
> the code is 0301 which I believe is misfire on cylinder one. which
> makes sense it back fires run like crap and no power. I replaced the
> spark plugs(easy and cheap fix). that solved the problem till I got
> after it and it started up again same code same symtoms does anyone
> have any clue what my next step would be what would be causing this. I
> don't really understand thenew system with no cap or rotor or wires
> please help......
>

billy ray

Okay.... You have 3 coil packs on a rail and are getting only one code you
can assume that it is not an electrical or coil problem as cylinder 1 and 6
fire off the same coil pack.

Did you blank the code with a tool or by disconnecting the battery?

Did you save the old plug?

What did it look like?

Was it unusually clean compared to the others?

Was it carboned or oily?

What does the exhaust look and smell like?

Is this a recent or existing problem?

Did it happen all at once?

What, if anything, did you do when or shortly before the problem started?

How many miles?

What kind are the new plugs?

Have you cleaned the throttle body?

Did you use an upper engine/ valve carbon cleaner (SeaFoam, etc?)



"jeepnfonz" <jeepnfonz@netscape.net> wrote in message
news:1155024110.444501.9630@m73g2000cwd.googlegrou ps.com...
> So I have on engine code on my 2001 tj sport with the 4.0 in line six.
> the code is 0301 which I believe is misfire on cylinder one. which
> makes sense it back fires run like crap and no power. I replaced the
> spark plugs(easy and cheap fix). that solved the problem till I got
> after it and it started up again same code same symtoms does anyone
> have any clue what my next step would be what would be causing this. I
> don't really understand thenew system with no cap or rotor or wires
> please help......
>

billy ray

Okay.... You have 3 coil packs on a rail and are getting only one code you
can assume that it is not an electrical or coil problem as cylinder 1 and 6
fire off the same coil pack.

Did you blank the code with a tool or by disconnecting the battery?

Did you save the old plug?

What did it look like?

Was it unusually clean compared to the others?

Was it carboned or oily?

What does the exhaust look and smell like?

Is this a recent or existing problem?

Did it happen all at once?

What, if anything, did you do when or shortly before the problem started?

How many miles?

What kind are the new plugs?

Have you cleaned the throttle body?

Did you use an upper engine/ valve carbon cleaner (SeaFoam, etc?)



"jeepnfonz" <jeepnfonz@netscape.net> wrote in message
news:1155024110.444501.9630@m73g2000cwd.googlegrou ps.com...
> So I have on engine code on my 2001 tj sport with the 4.0 in line six.
> the code is 0301 which I believe is misfire on cylinder one. which
> makes sense it back fires run like crap and no power. I replaced the
> spark plugs(easy and cheap fix). that solved the problem till I got
> after it and it started up again same code same symtoms does anyone
> have any clue what my next step would be what would be causing this. I
> don't really understand thenew system with no cap or rotor or wires
> please help......
>

jeepnfonz

Yes the plug was more dirty then the rest. the jeep has about 67,000
miles on it. See I was thinking for sure it was the coil, but that
makes sense thats its not. I replaced it with stock plugs. I think they
are autolites. There was one article I read said I should run champion
truck plugs. The plug I took out wasn't oily or yellow it was just
really black.

Is there a chance that I could have a bad cylinder. like low
compression, a bad valve or something. thanks for all the help so far
any more info would be great....

jeepnfonz

Yes the plug was more dirty then the rest. the jeep has about 67,000
miles on it. See I was thinking for sure it was the coil, but that
makes sense thats its not. I replaced it with stock plugs. I think they
are autolites. There was one article I read said I should run champion
truck plugs. The plug I took out wasn't oily or yellow it was just
really black.

Is there a chance that I could have a bad cylinder. like low
compression, a bad valve or something. thanks for all the help so far
any more info would be great....

jeepnfonz

Yes the plug was more dirty then the rest. the jeep has about 67,000
miles on it. See I was thinking for sure it was the coil, but that
makes sense thats its not. I replaced it with stock plugs. I think they
are autolites. There was one article I read said I should run champion
truck plugs. The plug I took out wasn't oily or yellow it was just
really black.

Is there a chance that I could have a bad cylinder. like low
compression, a bad valve or something. thanks for all the help so far
any more info would be great....

jeepnfonz

Yes the plug was more dirty then the rest. the jeep has about 67,000
miles on it. See I was thinking for sure it was the coil, but that
makes sense thats its not. I replaced it with stock plugs. I think they
are autolites. There was one article I read said I should run champion
truck plugs. The plug I took out wasn't oily or yellow it was just
really black.

Is there a chance that I could have a bad cylinder. like low
compression, a bad valve or something. thanks for all the help so far
any more info would be great....

billy ray

What about the other questions? While some might sound silly they were
asked for a valid diagnostic reason.

For example the question "What does the exhaust smell like?".... if you said
it smells 'sweet' that might indicate you are burning antifreeze....

What we now know is you have an '01 4 liter with 67k, may have new standard
Autolite plugs and the old plug was some form of black.

Do I understand that it backfires also? How often?



>Did you blank the code with a tool or by disconnecting the battery?

>Did you save the old plug?

>What did it look like?
Oily (wet) black or dry (carbon) black?

>Was it carboned or oily?

>What does the exhaust look and smell like?

>Is this a recent or existing problem?

>Did it happen all at once?

>What, if anything, did you do when or shortly before the problem started?

>Have you cleaned the throttle body?

>Did you use an upper engine/ valve carbon cleaner (SeaFoam, etc?)

PS: Please use quotes, other will jump in with ideas if they know how the
diagnosis is proceeding...




"jeepnfonz" <jeepnfonz@netscape.net> wrote in message
news:1155056034.787331.44690@i42g2000cwa.googlegro ups.com...
> Yes the plug was more dirty then the rest. the jeep has about 67,000
> miles on it. See I was thinking for sure it was the coil, but that
> makes sense thats its not. I replaced it with stock plugs. I think they
> are autolites. There was one article I read said I should run champion
> truck plugs. The plug I took out wasn't oily or yellow it was just
> really black.
>
> Is there a chance that I could have a bad cylinder. like low
> compression, a bad valve or something. thanks for all the help so far
> any more info would be great....
>