I have a 95 JGC 4.0, i just replaced the CAT and now my check engine light is on.
I went about 3 years without a CAT and i just put one back on it and the check engine light comes on after the engine warms up.
Please help.Could it be the O2 sensor?
it could be a lot of things, with a scanner what is the code.
Take it to almost any car part store (i.e. autozone) and they will check the error codes and give them to you for free. That's always a good place to start.
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