I was getting a 31 EGR position sensor insufficient voltage. I was running a 540cca battery so I upgraded to 880cca 1000ca battery. I cleared the system and tested it again. This time I got an 11 system "pass". does this mean all's well? Because if it does, something is really wrong because my volt gauge on the dash shows that I'm not charging when she's running (around 8-9). The truck turns over like a champ but the battery is minutes old. I'm so confused!!!

 

you won't get an EGR check engine light code, from having a small battery.... you need to drive the truck for a little while, and check for codes again.... fault code 31 is PFE, EVP or EVR circuit below minimum voltage.... check for loose or corroded connections on the sensor, but in the mean time, take a look and read up on this
http://www.fordfuelinjection.com/?p=35

 

I was just hoping. I needed a bigger battery anyway. Does the 11 mean anything? My gauges show very little charge. The smaller battery was charging just fine. I think the idle might be a vac leak. Idle jumps up and down around 1000. The 11 just threw me.

 

11= system pass. This just means that the computer sucessfully ran diagnostic and there are no codes. There will be no code if your alternator isn't charging properly, the computer doesn't monitor the alternator.

 

Thanks. What kind of volts/amps should read if I test the diode?