Cylinder 1-6 misfiring
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Year: 1999
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Cylinder 1-6 misfiring
now I just got codes P0300,P0301,P0302,P0303,P0304,P0305,P0306.Multiple misfires all cylinders! before anyone asks 3 months ago it got new wires ,ignition cool,spark plugs "champion", CPS sensor new hoses new radiator and a ton more and not to mention new head gasket head was machined and all new seals etc...Where do I start? And all those codes really say are misfiring not what's causing it to misfire.So yeah troubleshooting I assume but where do I start.Or should I take it to a dealership and have them make it pur
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Year: 1999
Model: Cherokee
Engine: 4.0
You have one "common" problem causing all cylinders to misfire.
The first thing I do with this type of problem is to verify fuel pressure. I will guarantee you that any technician worth their salt will do the same.
Many parts stores will rent you a fuel pressure gauge inexpensively. I believe the fuel pressure spec for the 96 is 49 psi, plus or minus 5 psi......but some early 96 may have the old fuel system where the spec is 31 psi. So you need to determine that.
Start there. Let us know what you find. Good luck!
The first thing I do with this type of problem is to verify fuel pressure. I will guarantee you that any technician worth their salt will do the same.
Many parts stores will rent you a fuel pressure gauge inexpensively. I believe the fuel pressure spec for the 96 is 49 psi, plus or minus 5 psi......but some early 96 may have the old fuel system where the spec is 31 psi. So you need to determine that.
Start there. Let us know what you find. Good luck!
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You have one "common" problem causing all cylinders to misfire. The first thing I do with this type of problem is to verify fuel pressure. I will guarantee you that any technician worth their salt will do the same. Many parts stores will rent you a fuel pressure gauge inexpensively. I believe the fuel pressure spec for the 96 is 49 psi, plus or minus 5 psi......but some early 96 may have the old fuel system where the spec is 31 psi. So you need to determine that. Start there. Let us know what you find. Good luck!
I need to do this sooon now when I idle especially come up to a light or a stop it putts real rough and sounds like it's gonna stall but it doesn't.
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Assuming we're working on a 1996 Jeep Cherokee I'd start with checking out the rotor button and cap visually, test the coil and cps. Betcha it's one of those.
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Yeah this weekend I am just gonna get a new cab and rotor wires plugs putting new injectors on upgrading the manifold and ordering a new IAC now after I do all that and if it is still doing the same thing I will go to the CPS. As far as fuel pressure it's at 40 PSI is that good someone said fuel pressure spec for the 96 is 49 I believe I have a later 96 it has the over head console and all don't think earlier ones have that.
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Yeah this weekend I am just gonna get a new cab and rotor wires plugs putting new injectors on upgrading the manifold and ordering a new IAC now after I do all that and if it is still doing the same thing I will go to the CPS. As far as fuel pressure it's at 40 PSI is that good someone said fuel pressure spec for the 96 is 49 I believe I have a later 96 it has the over head console and all don't think earlier ones have that.
If the cap and rotor look good then test the coil and cps. Don't just blindly replace it.
40psi is acceptable.
Yes. That's why I suggested looking at those parts.
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Don't do all that until you figure out the cause of the issue. Adding multiple parts at once just complicates things. Just pull the cap off and look at it. Take a picture of it. Post it. If the cap and rotor look good then test the coil and cps. Don't just blindly replace it. 40psi is acceptable. Yes. That's why I suggested looking at those parts.