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2008 Ford F-150 4.2L P0352 Code: No Spark, Misfire, Open Loop - Diagnosis & Fix

Model: 2008 Ford F-150 Fault Code: P0352 Posted: 2016-04-12 09:36

I own a 2008 Ford F-150 with a 4.2L engine and am currently experiencing a persistent P0352 diagnostic trouble code. I've already replaced the spark plugs, ignition wires, and the coil pack, but the P0352 code remains. The vehicle shows no power, severe misfires, and is stuck in open-loop mode with all fuel trim and oxygen sensor values reading zero. When connected to an OBD2 scanner, it refuses to exit open loop and displays abnormal data for both fuel trims and oxygen sensors. I've tested spark across all cylinders and found that cylinders 3 and 4 have no spark despite the coil pack being replaced. All four oxygen sensors are showing readings of 0.0015 V, which is outside normal range. Fuel trim values (LTFT and STFT) are at zero — this is highly suspicious as it indicates a complete lack of feedback control. I suspect an issue with the ignition signal wiring from the engine control module to the coil pack. I've tested the coil's connections under KOEO conditions, but the results show that only one wire (violet/white) has voltage when the connector is unplugged, and the control/signal wire (red/ltblue) does not have proper ground. I'm seeking expert advice on how to properly diagnose this issue. Is it a wiring fault? A faulty signal from the ECU? Or could there be an internal coil pack failure despite replacement? Any guidance on next steps — such as checking freeze frame data, performing a drive cycle, or testing with proper diagnostic tools — would be greatly appreciated.

Related fault codes
P0352
Comments (7)
Anonymous 2016-04-12 10:07

Is there spark at cylinder #2 (passenger side center)?

Anonymous 2016-04-12 11:47

Yes, spark is present on cylinder #2.

Anonymous 2016-04-12 11:49

All fuel trim and oxygen sensor values are showing zero — this is highly abnormal. Oxygen sensors should display a voltage signal between 0.1V and 0.9V under normal conditions. A reading of 0.0015V suggests a wiring or sensor fault.

Anonymous 2016-04-12 12:42

A fuel trim value of zero is extremely suspect — it indicates no feedback from the engine control system, which should be active during operation. An oxygen sensor reading of 0.0015V is not valid; sensors must have a voltage signal to function properly. This points to either faulty wiring or a data transmission issue. Suggestion: Rescan the vehicle, review freeze frame data, clear codes, perform a full drive cycle, and then rescan to see if the code returns with real-world operating conditions.

Anonymous 2016-04-12 12:52

I tested spark on all cylinders and confirmed that cylinders 3 and 4 have no spark. I replaced the coil pack, but the issue persists. All four oxygen sensors are reading 0.0015V — this is not normal. Fuel trim values are at zero across both LTFT and STFT.

Anonymous 2016-04-12 13:15

Cylinders 3 and 4 appear to be paired, which suggests a possible wiring or signal path issue. For the coil pack (which has four wires), perform these tests under KOEO conditions: 1) With connector plugged in: All four wires should have 12V. Confirm this — yes or no? 2) With connector unplugged: Only one wire (violet/white) shows voltage — confirm this — yes or no? 3) Check the unpowered control/signal wire (red/ltblue) for proper ground connection — confirm this — yes or no? These results will help determine if the issue is in wiring, signal transmission, or ECU communication.

Anonymous 2016-04-13 16:34

Thank you all for your input. I've now confirmed that the wire carrying the signal from the engine control module to the coil pack is not transmitting a proper ignition signal — this explains why cylinders 3 and 4 have no spark despite a new coil pack installation.