I have a 96 s-10 4.3. It started with a P0300 code so I replaced the basic tune up stuff (plugs wires cap and button) cleared code and test drove, all seemed good but the light came back on the next day. It occassionally adds a P0340 and most recently started giving a P0102 code. The P0102 is a result of the ENG fuse blown, I replace the fuse and the P0102 code clears but after about a day the fuse blows and that code comes back. Any help on these codes and why the ENG fuse keeps blowing?......THANKS

 

Help Iam am having the same problem. Replaced cam sensor,new MAF, cap rotor button and still blws #5 fuse.

 

In a '96, the ENG fuse (#5 - 20A) powers the CMP sensor, EVAP purge valve, EVAP vent valve, all 4 O2 sensor heater circuits, the EGR valve, the MAF sensor, and a few leads to the PCM. These are all on circuit 539. If any one of these items and/or the wiring between any one of these items and the fuse is shorted to ground, it would cause the fuse to blow.

 

Just went out and cleared the codes p0102 and p03040 and they stayed off. The truck is cold now and the fuse did not blow. When the truck got up to normal temp earlier today the #5 fuse blow ed and the codes came back on.??

 

has anyone had this problem before? Fuse blows and check engine light comes on when temp gauge gets to about 125deg

 

What are you waiting for? Get in there and start diagnosing the circuit. Unplug everything that I mentioned and see if the fuse still blows. Plug each item in individually and measure the amperage going through the circuit, writing each one down. See if you can locate the bad component through a process of elimination.

 

I unplugged all 6 of the sensors and started the truck up. When the water temp got to about 140-150 deg. I put the truck in reverse and the fused blowed. Do you think it is a wire short or main computer problem?
Thanks for any help.

 

Took it to the shop today and the mechanic took a Short Checker and found the problem. The wiring harness on the passenger side frame rail going to the O2 sensors had been touching the manifold and finally melted into the wire. When it cooled off it would un stick until it got hot again. He said it looked like it was still routed as from the factory but it still got to the heat. Hope this helps someone else down the road.