1997 Jeep Wrangler Cylinder 1 Misifre
#1
10-08-07, 07:18 AM
1997 Jeep Wrangler Cylinder 1 Misifre
engine light keeps coming on for cylinder #1
I put new plugs, wires, cap & rotor--same problem
also replaced the #1 injector for not firing
still code 301 for cylinder #1??
I need some help
I put new plugs, wires, cap & rotor--same problem
also replaced the #1 injector for not firing
still code 301 for cylinder #1??
I need some help
#2
10-08-07, 08:32 AM
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Youre going to need to do some more testing. First compression test. Test all cylinders and compare. Post back those results. Also if you have the capability Cylinder leakdown test is very important. You could have a burned valve and no tune up is going to fix that. There are other mechanical issues that can cause this but they are major internals. Do the basic testing first and then get back to us. What engine do you have so we know what we are working with here.
Hope this is helpful to ya,
Billy
Hope this is helpful to ya,
Billy
#4
10-08-07, 10:30 AM
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I am unable to find what the compression is supposed to be. However it should never be more than 15% different from any other cylinder.
Hope this helps ya,
Billy
Hope this helps ya,
Billy
#5
10-09-07, 06:23 AM
1997 Jeep Wrangler Sport
hey whats up bro, I did the compression test cylinder #1 is at 142 and the other 5 cylinders at 150
next thing I removed the spark plug and found that it was full of carbon (not wet just dry black dust) the other 5 plugs looked clean
and I just put the plugs on 2 days ago
is this telling me a bad valve? what do you think
thanks for your time
next thing I removed the spark plug and found that it was full of carbon (not wet just dry black dust) the other 5 plugs looked clean
and I just put the plugs on 2 days ago
is this telling me a bad valve? what do you think
thanks for your time
#6
10-09-07, 07:36 AM
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8psi variance should not be enough to cause a misfire. Black dust on the spark plug indicates carbon fouling. It is also commonly known as Cold Fouling. It is a condition cause by sticking valves or defective spark plug cables, or a clogged air filter element. Since it is only 1 spark plug that has this condition, Im betting you have a sticking, burned valve or a weak valve spring.
How does it run? Can you feel the misfire? Are you able to perform a cylinder leakage test? What brand of spark plugs are you using? Please dont tell me Bosch.
Billy
How does it run? Can you feel the misfire? Are you able to perform a cylinder leakage test? What brand of spark plugs are you using? Please dont tell me Bosch.
Billy
#7
10-09-07, 08:26 AM
1997 Jeep
It does have a small misfire at idle but runs good
as far as plugs --yes they are bosch
air filter is new, wires are new
so its in the head --thats what your guessing
im in the same boat on thinking the valve
that could be the only thing left causing the plug to foul
or look like that?
as far as plugs --yes they are bosch
air filter is new, wires are new
so its in the head --thats what your guessing
im in the same boat on thinking the valve
that could be the only thing left causing the plug to foul
or look like that?
#8
10-09-07, 08:44 AM
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Most likely YES thats about all thats left. I would get those Bosch plugs out of there soon..... They dont fare very well in much of anything but European cars and lawnmowers... LOL. Champion is the correct plug for this vehicle. I would stick with whats time tested.
Good Luck,
Billy
Good Luck,
Billy
