2012 Malibu Response LX Service Required

[albernhagen]

Hello -- I have a 2012 Malibu Response LX that has started throwing service required on the in-dash display.  Boat has been running normally all season until this started.  Taking it off the lift the other day, it was pulsing a bit at idle.  Otherwise, it seemed okay.  Then pulling a skier, the power cut out while taking off.  Let it sit for a bit and then it worked fine.  Since then (the rest of that night and another day), I continue to see the intermittent behavior.  Service required continues to show up regularly even if I clear the screen.  Sometimes it pulls fine, sometimes it cuts power pulling a skier out.  Twice it has even idled at a much higher RPM than normal.

Reading online, it seems like there were a lot of CAT sensor issues around 2008, but not sure if those would apply in a 2012 Response LX.  I've certainly never done any work on that part of the boat, so not sure where it to even begin when looking at cat issues.  I've tried to gather fault codes.  All but one time, there have been 0 codes.  Given I've seen service required maybe 30 times, this might not mean anything or be related, but just once I was able to get the following:

PPS1
SPN        91 CM 0
DATA VALID BUT
BELOW NORMAL RNG
FMI 18 OC 13

Any suggestions of where to begin?  The nearest dealer is at least an hour and a half away and I'm generally not too afraid to try some fixes myself first before paying a dealer to try things out.

Thanks!

Edited May 30, 2023 by albernhagen

[BuFootin]

Check all ground connections on the engine and under dash.  Always a good place to start troubleshooting intermittent issues.

[albernhagen]

I finally found some error code references (technically from an 09/10 Indmar manual) suggesting that this might be the TPS, which seems to correlate with other forum posts, so that seems like the first thing for me to try at this point.

[csleaver]

SPN 91, FMI 18 - FPP1 Lower than FPP2 fault occurs when the ECM reads a certain difference between the pedal position 1 and pedal position 2 sensors from the shift/throttle controller.  There were some Malibu service bulletins about the ZF shift throttle controllers in 2012 that required replacement.  There could be a system voltage problem, loose or worn connections, or faulty sensors in the throttle control causing the issue.

[albernhagen]

I took apart the throttle control last night.  I think this is the TPS?  Does anyone know if it's possible to replace just this?  It doesn't look like any of the Indmar ones.  Unless it's deeper in the throttle itself?  It seemed like this one given the 6-pin connector.  I have a Teleflex MV-=3 throttle.  I've had no luck finding a replacement part yet.  This seems to be the part but can only be bought in bulk: https://www.hindlecontrols.com/product/vsense-non-contact-sensor/

Edited May 31, 2023 by albernhagen