P0122 P0453 P01122 codes?

2003 OLDSMOBILE ALERO
195,187 MILES • 3.4L • AUTOMATIC
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RALPHPHIPPS22
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I got these three codes and tried all sorts of stuff. I tried doing a lot of tests and I’m starting to suspect I cross wired the fuel tank harness
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Jul 7, 2026 at 6:31 PM
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STRAILER
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Can I ask what repairs you have made so we don't start down the wrong trail?
Jul 7, 2026 at 6:40 PM
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RALPHPHIPPS22
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I spliced in a new connector to the fuel pump due to a bad connector and I also done a new MAF connector. I get 0 09 volts back probing it
Jul 7, 2026 at 7:12 PM
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RALPHPHIPPS22
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Back probing at the grey 5 volts reference wire for the TPS sensor
Jul 7, 2026 at 7:12 PM
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RALPHPHIPPS22
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Update. We are now reading 3.4 volts at the connector pins for the TPS
Jul 7, 2026 at 7:37 PM
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STRAILER
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Have you replaced the throttle body sensor? That is what I would do, then clear the codes. The fuel level sensor is a separate issue. Also, check the engine wiring harness grounds to the intake/block.
Jul 7, 2026 at 9:39 PM
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STRAILER
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You can do a continuity test from the throttle body tot eh PCM as well.

https://www.2carpros.com/articles/how-to-check-wiring/

Here are the wiring diagrams...Also, check the ECM wiring connector for corrosion. I have seen this as well.

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Jul 7, 2026 at 9:42 PM
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