I keep blowing the 02 sensor fuse. The sensors have been replaced and we can't find any bad wiring. The next option was to repair/ replace the. ECM. I can't find any videos or photos of where the part is located on the car. Any help here would greatly appreciated.

 

If you are replacing fuse 33 in the fuse box under the hood that powers the O2 sensor heaters - That fuse powers the vacuum pump also. Does your vacuum pump work? 8/84 is the vacuum pump switch, 6/114 is the pump, 7/15 and 7/82 are the O2 sensors.

 

I don't think I'm having any issues with that. What would be the symptoms be?

 

The vacuum pump does not work. The switches commonly break and make the pump run until it seizes up and possibly shorts out. Then it blows the fuse (#33 in the diagram that also powers the O2 heaters.)

To test: Turn ignition on, don't start car. Pump the brake pedal - if it gets hard after a few pumps - the vacuum pump is not working. If it stays the normal soft feel - the vacuum pump is working. Or find and visually inspect the switch and pump - you can jump across the two wires in the harness to the switch to manually run the pump. If it takes a while to blow the fuse - just unplug the vacuum pump switch to prevent current from going to the pump - and see if the fuse continues to blow.

 

So if the brake gets hard, then do i need to replace the vacuum pump or is this a sign of the ecm going out?

 

If the vacuum pump does not work - you need to figure out why. (is it seized, is the switch is bad - or there's no power to the switch because of a problem with other items on the fuse causing it to blow, etc.) The ECM has nothing to do with the vacuum pump. Stop thinking about a bad ECM - you don't want that to be the cure, it's not a common failure. You may have already replaced O2 sensor you did not need to - so

Look at the wiring diagram. Power goes from fuse 33 to the vacuum pump switch, which if turned on (due to low vacuum in the connected hoses or a broken switch) sends power to the pump, and the pump is grounded completing the circuit.

How long does it take before fuse 33 blows?

 

Vacuum pump was working. Found out that the wrong size fuse installed. Replaced the fuse, reset the check engine light. I drove it for 60 miles and no light. It passed inspection.