2005 MC 197 help...

[rfa]

Looking for help for a friend's 197 with Indmar MCX. Yesterday engine check came on and sent engine to limp mode...it happened twice when he was skiing. ..once he was back in the boat it ran fine...I assumed a random event with no relation to the skiing. Tonight I went out with him to witness it myself and was surprised with the symptoms. Boat ran fine to the slalom course (about 1 mile). He got in the water and I tried to get him up 3 times and engine check/limp mode came within less than 50 yds each time. He got back in the boat and it ran fine all the way home...looks like some load related sensor but I have no clue on what to even look at. He has no capability to connect it to a computer for diagnosis....any thoughts at all?

Thank you

[rfa]

Also tried to pull him up with and the PP Stargazer system on and off. No sure it's relevant but thought I'd add that. Thanks

[bbirlew]

I have quite a different boat ('94 nautique with throttle body injected 5.8HO PCM) but had the same symptoms... For me it was a bad coil pack.

A buddy had a spare one and I swapped it out with one side then the other until I found the culprit.

 

I think the things that triggered limp mode on my boat were temperature or oil pressure sensors. (Maybe knock sensor on a Gm block?)

I was also told to check spark plugs and wires. (Start with the inexpensive stuff and work your way up)

 

I was told to first disconnect the temp sensor and if I was still experiencing symptoms try the oil pressure. The signal goes high when trouble is detected so it should run fine without them connected. These are different from the gauge sending units so you will still have your dash gauges to keep an eye on things.

Check for corrosion where the plug wires connect to the plugs and coil pack. Emery paper will clean up the surfaces.

 

Again, a much older boat than yours, but some of it may be applicable?

Good luck!

[RichardDoane]

@rfa - engine temperature is ok ? Impeller is good and there is no debris restricting water flow through the transmission cooler ? Most limp mode issues are temperature related.

[rfa]

Thanks. ..temperature and pressure Ok. Checked impeller and cooler. Also my friend had recently replaced plugs wires cap and rotor. I'll pass the info to him...thank you

[oldjeep]

Oil level? While it doesn't go into limp mode, the 04 LXI I ski behind throws warning beeps when cornering at the end of the course if the oil level isn't high enough - I assume it sucks a little air and drops the pressure momentarily.

[TallSkinnyGuy]

You should post this on the Mastercraft Team Talk forum. Extremely helpful and knowledgeable group there.

[skristo]

Thanks you all for the advice. After changing the in tank fuel filter, running 93 octane, knock sensor, water temp sensor, verifying transmission temp sensor for proper operation, and ruling out the oil pressure sensor, I was going over this with a friend and I asked, could it be a bad ECM? He said did you check the ECM ground? I put a 5/8 wrench on the 3 grounds on the bell housing. The one for the battery ground was good but the other two, that have grounds for the main harness, needed to be tightened. A couple of turns with the wrench and My problem went away! Lesson learned; I plan on checking these as part of my spring routine, to get my boat ready every year.

I hope this post will help others.

thanks again for the help

[Jordan]

Glad that you found the problem...poor grounds can cause all kinds of crazy issues.