Detail: My daughters 2004 jeep grand cherokee failed emissions. codes were 2 lower o2 sensors and 1 upper. but i noticed fuse in engine was blown, replaced fuse, and blows again. disconected all 4 sensors, fuse still blows. i've looked at wiring and no areas where wires are bad. any ideas ???
Solution: Which fuse is blowing? , Hi, a 6ya Mechanic can help you resolve that issue over the phone in a minute or two. Best thing about this new service is that you are never placed on hold and get to talk to real repair professionals here in the US. click here to Talk to a Mechanic (only for users in the US for now) and get all the help you need. Goodluck! , You've probably solved your problem by now but if not, you really need to buy a cheap digital multimeter. It will help you in this kind of situation and others. Connecting it between the output side of the fuse for that circuit and ground can let you start pulling connectors until the low resistance causing the blown fuses goes away. Experience with this kind of troubleshooting helps so you may be a little uncertain at first. They can be had at auto-parts stores, Radio Shack, or if you are lucky enough to have a Harbor Freight tool store near you, they often have the things for $3 and while not exactly precision instruments, they are adequate for most anything one can do at home. , Your thermostat is stuck closed. It needs to be changed right away. By the way the operating temp on that motor is 160 degrees so you are running hot you have just been lucky so far. Good Luck , Hi my name is Allen! I work for a Dodge Dealership. There are no torque specs for the upper or the lower ball joints on any of the Chrysler Vehicles. As long as you get them as tight as you can they will be fine, don't worry they are held in by road force anyway. Note: Be careful that you don't strip-out the nuts by getting them to tight. For further asistance you may reach me at FixYa! , If you have trouble codes stored in your cars computer for O2 sensors a fuse will not fix it. One or all of the O2's may need to be replaced. There are test that can be done to confirm which one. , Your OBD codes indicate a lean signal on both banks. (I'm assuming you have a 3.0L) Bum O2 sensors could do this. Other ideas might be to check for air leak in the exhaust as well as intake. (Your buddy did a thorough job on air inlet) Did he check PCV, EGR and around the throttle body. Some of the exhaust gaskets can go slightly and mess up the O2 signal. Good luck guys. (Been there!)