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Discussion Starter #1
Hi, we have a 2005, we have been seeing our gas mileage decline. It has gone from high 30s per gallon now to low twenty's now. We went to advance and had codes read. Came up with....
P0121-Throttle position sensor
P0130-02 sensor bank 1 sensor 1
P0171-Bank 1 system too lean
P0300-Random multiple misfire
P0420-Catalyst system below threshold Bank 1
P0455-Evap emission system leak detected(gross leak/no flow)
P0461-Fuel level sensor A circuit range
P0520-Engine oil pressure sensor circuit
P1680-Acceleration Pedal system performance.

Engine also sputters after a tank fill up. What in the world is wrong with this thing now?

Thanks your your reply
 

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Start by checking all the fuses in the underhood fuse block especially the EXH fuse.



---------- Post added at 01:06 PM ---------- Previous post was at 12:23 PM ----------

You might even find the Evap canister fuse burnt.



Sometimes rodents, including squirrels will chew wire insulation so you might want to check wiring around Evap canister for frayedor bare wires.
 

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Discussion Starter #4
Checked Fuses

Thanks for your replys. We checked the fuses. No problem there that we can see. Any other ideas?
 

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Only other possibility is that you lost an engine ground.

---------- Post added at 02:04 PM ---------- Previous post was at 01:59 PM ----------

To have so many codes at once you lost a ground or B+. There's one on the radiator support near driver's side headlight, one on the sub frame (mostly for lights) one under the coolant reservoir (wipers, washerpump) one on the driver's side inside shock tower (Power steering, ip hvac) But the most important one is where they meet at the engine in front near where the transmission bolts on.

 

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Hope you don't mind. Here are a few more pictures of this ground.

 
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