Code P0452, Fuel Tank Drop

[H2ummer]

Originally Posted by HUMTECH

Ignition OFF, disconnect the harness connector at the FTP sensor.
 2. Ignition OFF, test for less than 5 ohms between the low reference circuit terminal 2 and ground.
⇒ If greater than the specified range, test the low reference circuit for an open/high resistance. If the circuit tests normal, replace the ECM.
 3. Ignition ON, test for 4.8–5.2 volts between the 5-volt reference circuit terminal 3 and ground.
⇒ If less than the specified range, test the 5-volt reference circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the ECM.
⇒ If greater than the specified range, test the 5-volt reference circuit for a short to voltage. If the circuit tests normal, replace the ECM.
 4. Verify the scan tool FTP sensor parameter is less than 0.2 volts.
⇒ If greater than the specified range, test the signal circuit terminal 1 for a short to voltage. If the circuit tests normal, replace the ECM.
 5. Install a 3A fused jumper wire between the signal circuit terminal 1 and the 5-volt reference circuit terminal 3. Verify the scan tool FTP sensor parameter is greater than 4.7 volts.
⇒ If less than the specified range, test the signal circuit for short to ground or an open/high resistance. If the circuit tests normal, replace the ECM.
 6. If all circuits test normal, test or replace the FTP sensor.

HumTech,
In your experience, would you say it is the ECM more times than it is the FTP sensor? Still have to drop the tank to make those measurements, so probably should just replace the FTP if you have the tank down anyway? It is not that much.

Oh and I guess if you replace the ECM and buy one online, that you cant just replace it, you have to take it to the dealer to get it programmed before you install it?

Thoughts?