And injector #8 would fail a Cylinder Contribution Test (CCT) with a Diagnostic Trouble Code (DTC) of P0284. Idle Missįord’s new gray, recall-replacement 7.3 CPS created a very noticeable idle miss. A telltale sign that your 7.3 cam sensor has failed.Īfter 2002 the 7.3 diesel’s instrument cluster changed and the “dead” tach was no longer an indication that the CPS had failed. This is the exact scenario that has many 7.3 Powerstroke owners, myself included, carrying a spare CPS in our glove boxes.Ī couple quick ways to tell if it’s your cam sensor is dead: Tach needle doesn’t move during crankingĭuring cranking, the tachometer needle on a pre-2002, 7.3 Powerstroke won’t move. Then your 7.3 injectors won’t fire and your truck won’t start.
And if the PCM doesn’t know where the cam is in the cylinder rotation it won’t send an injector signal to the Injector Driver Module (IDM). Then your engine will crank but not start.īecause if your 7.3’s cam sensor is toast, it can’t send a signal to the PCM.
One minute you’ll be driving down the road with no issues and the next your trusty 7.3 liter diesel will simply die.
Failed 7.3 CPS sensors have left many 7.3 Powerstroke drivers broken down along the side of the road. So, guess what happens if your 7.3 CPS is malfunctioning? 7.3 Cam Position Sensor Symptomsĭying at idle over a period of weeks or months can signal an imminent 7.3 CPS failure. It also helps in adjusting things like RPM to ensure smooth idle and operation of the engine. Then the PCM can deliver the fuel at the precise moment it’s needed. Since the cylinder #1 and cylinder #4 indicator windows are narrower and wider, respectively, than the other windows on the cam wheel, the 7.3 cam sensor can tell which cylinder is about to hit top dead center- TDC. The magnet’s job is to sense the spokes and gaps (windows) on the camshaft wheel. The inserted end of the 7.3 CPS is a magnet.
Knowing this allows the engine powertrain control module ( PCM) to adjust fuel injection timing to provide smooth combustion to your diesel truck.Īnd that means that it helps your 7.3 Powerstroke diesel engine deliver fuel to the right cylinder at the right moment in the timing sequence. Simply put, the 7.3 cam position sensor identifies which cylinder is at top dead center-the combustion stroke.