Stalling after reversing

[MalibuMike]

2007 5.7 with. Dp-s. Put the boat in reverse and bring the RPMS up to back up. Back to neutral and get a stall. Any idea where to start?

 

[dubs283]

When was the last full tune up?

 

[MalibuMike]

When was the last full tune up?

Its been a year and half since spark plugs were changed. I change the cap and rotor about every 6 months since Napa has lifetime warranties on their Echlin line of caps and rotors. Spark plug wires are older. IAC has never been cleaned.

 

[jimmbo]

Perhaps you are backing up too fast and water is being pushed back up the Exhaust, and the Backpressure is strangling the engine

 

[mvn]

Same issue with a 2008 5.0L. It ended up being a bad IAC. Only an OEM Merc replacement solved the problem.

Mark

 

[dubs283]

Its been a year and half since spark plugs were changed. I change the cap and rotor about every 6 months since Napa has lifetime warranties on their Echlin line of caps and rotors. Spark plug wires are older. IAC has never been cleaned.

Piecemeal tune up over time isn't a good strategy. Would question the quality of napa brand components as well, might be okay for an older auto but your boat needs special attention

Is this mpi or tbi? HEI/EST ignition allows for timing adjustment

Have you inspected/replaced fuel filters?

Not a bad idea to remove, inspect and clean the iac