Question I have a 1998 Ext. Cab Chevy K1500 4X4 5.7 Vortec. My problem is that the fuse ENG-I keeps blowing. When it blows, the check engine light comes on and gives 2 codes. P0102 (MAF Low Input) and P0340 (Camshaft sensor circuit fault). I noticed that this knocks out power to the MAF sensor as I have checked it with a volt meter. As a result the truck hesitates and sometimes lopes at idle. I can replace the fuse and clear the codes and it runs perfect. Then I can drive it usually 10 min to 30 min or so and it blows again setting the 2 codes above and running poorly again. Something is obviously shorting out somewhere. Please give me some ideas of what and where to look. I dont know if a sensor somewhere is shorting intermittently or a wire is grounding out somewhere. Any help is appreciated. I also have an Autoxray 4000 that I can, and have used, but I am still learning how to use it efficiently.
AnswerHi
I can tell you the items that fuse feeds, and you can locate short. PAY special attention to ANY wire harness that may be touching Exhaust manifold.
Fuse feeds
1)EVAP canister vent valve (located on drivers sdide engine compartment, front on top of "charcoal canister)
2)MAss Air Flow Sensor
3)Camshaft position sensor
4)A.I.R. Recirculation relay (Calif. Emissions)
5)Evap Purge Solonoid (Passanger side on intake manifold half way down, right befor coil)
All four heated oxygen sensors (Bank1 #1, Bank1 #2, Bank1#3 and Bank2 #1)
I would unplug EVERYTHING first and see if it blows.
IF so NONE of the sensors are faulty.
If not it is one of the sensors.
I Hope this helps.
Good Luck
Pawl
