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2003 Ford F-150 P1797 Code: Engine Cranks and Runs at Idle But Fails to Accelerate

Model: 2003 Ford F-150 Fault Code: P1797 Posted: 2020-04-23 16:59

I own a 2003 Ford F-150 with a 4.6L engine. After performing an engine overhaul, the vehicle cranks and runs smoothly at idle. However, it fails to accelerate past idle speed. The check engine light is triggered by a short-to-ground fault, specifically code P1797 (Neutral Switch Circuit Malfunction). Despite the engine running fine under load, the transmission does not respond properly when attempting to accelerate. I'm seeking advice on how to diagnose and resolve this issue, especially since the problem appears after mechanical work was completed.

Related fault codes
P1797
Comments (2)
Anonymous 2020-04-24 08:01

P1797 = Neutral Switch Circuit Malfunction. This code indicates a fault in the neutral position sensor circuit, which can prevent proper transmission engagement during acceleration. Check for loose wiring or corrosion at the neutral switch connector, especially after engine overhaul where harnesses may have been disturbed.

Anonymous 2020-04-24 13:23

I have a 2003 Ford F-1 T50 with a 4.6L engine. After an engine rebuild, it cranks and runs fine at idle but fails to accelerate — I'm seeing code P1797. I'm mechanically experienced but not well-versed in electronic systems. Has anyone else encountered this issue after an engine overhaul? Any suggestions on how to troubleshoot the neutral switch or related circuits?