Crank sensor relearn

[Blowncoupe]

Has anyone changed a crank sensor and had to have it relearn to the ecm? 
have to change one today on a hh383  need to know the procedure if there is one

thanks

[csleaver]

The crank position sensor is just a standard hall effect device that should not require any kind of "re-learning", but if you have catalyst exhaust it is important to clear the fuel adaption, misfire counter, and trouble codes using diacom after a repair has been done to the fuel or ignition system.  Turn the ignition off for at least 5 seconds after clearing the codes or adaption, then restart the engine for it to take effect.

Edited April 10, 2021 by csleaver

[Blowncoupe]

I do have a catalyst exhaust. Thanks for the reply 

[JZ Rlxi 2007]

On 4/10/2021 at 9:27 AM, csleaver said:

The crank position sensor is just a standard hall effect device that should not require any kind of "re-learning", but if you have catalyst exhaust it is important to clear the fuel adaption, misfire counter, and trouble codes using diacom after a repair has been done to the fuel or ignition system.  Turn the ignition off for at least 5 seconds after clearing the codes or adaption, then restart the engine for it to take effect.

Hi.  Useful information, thanks.

I replaced my crankshaft sensor a while back because the engine would shut down after about 30 minutes, and sent a code about this sensor.  This is on a 2016 Response Txi with 5.7 Crusader engine.

Sometime after replacing the CPK, I started getting sporadic misfire codes, only when ambient temperatures are about 80F and above, and the boat has been pulling a skier for a while.  There is also a very infrequent engine stumble at idle.  The engine runs strong, smooth, and you cannot feel or hear any of the misfires.  Do you suspect that NOT having used a diacom to clear the fuel adaption, misfire counter, and trouble codes could be causing these ongoing minor concerns??

I have a friend with a diacom, are there instructions for clearing ECM of these codes?

[csleaver]

It is definitely possible, but many other things can cause a misfire fault or the running issue you are having.

If you have access to Diacom, first use it to see if there are any active or previously active fault codes, then check to see if your fuel pressure and cam retard angle are within specification.  The misfire and fuel adaption clear is on the test tab page.  You can also make a diacom recording to email to your dealer or a factory representative.

The Diacom injector kill test can be used as a quick way to determine if all cylinders are making power.  I usually do it around 2000-3000 RPM and look for a similar drop in RPM from each cylinder when the injector is turned off.  If a cylinder RPM does not drop during the test, then it is suspect.

Many things can cause a misfire fault:

. Broken or worn spark plugs, wires, coil, cap, rotor, or wrong cam angle causing weak or un-timed spark.

. Low or very uneven cylinder compression.

. A plugged or stuck open fuel injector.

. Low or high fuel pressure.

. An intake leak or exhaust leak near an exhaust valve.

. Improper oil level that can cause issues with hydraulic lifters and valve timing.

. Excessive drivetrain vibration.