Alarm after reaching cruising speed

[Harbs]

My 2006 Tige 22V steady alarm goes on after a few minutes at above 20 mph (~3000rpm). Dealer said it was a knock code and changed the spark plugs and rotor. This did not fix the problem, any thoughts?

[WYTige?]

I had a similar problem that would only happen at about 4500rpms. I would shut it down restart and the alarm would disappear. Mine turned about to be the starboard side knock sensor. Replaced it for $30 at the auto parts store and no more issues. i spent over $600 going to dealers trying to find the answer and I fixed it for $30.

[JCP]

Not sure about marine electronics but if it was an automotive application there would not be a code set for detecting a knock. Codes for a bad knock sensor however are common and will usually specify what banks sensor is bad. If the sensors are hard to get to (under the intake manifold) we will usually replace both sensors and the wire harness going to them. The harness is just as likely to go bad as the sensor.

[ericinmich]

Knock sensor codes are more common on marine packages because the sensors are typically removed tonwinterize. The connectors or sensors are the same ones as used by autos around that time and I can guarantee that the quote packages were not specified for more than a few connection cycles. Most connectors are sourced for around ten, including the ecu's.

The codes will be set for too much knock detected for too long, and continuity. Later ones added low signal.

[IDBoating]

The connectors or sensors are the same ones as used by autos around that time and I can guarantee that the quote packages were not specified for more than a few connection cycles. Most connectors are sourced for around ten, including the ecu's.

That is an EXCELLENT observation. While working on some of our marine projects here (including the replacement Tige touchpad), we discovered from their spec sheets that the hyper-expensive Duetsch/Amphenol connectors are only rated for 100 connection cycles. Granted this isn't a USB charging connector on someone's cellphone, but still... if you're paying over ten bucks for the connector housing and fifty cents per machined contact, might as well drop a few more percent into giving it some longevity.

[Harbs]

Thanks for the thoughts. Is there a device I can buy that will tell me the codes that are causing the steady alarm problem? Dealer replaced the spark plugs and rotor but did not change any sensors. What is a connection cycle and is a knock something to be concerned about besides the irritation of the steady alarm?

[IDBoating]

"Connection cycle" in this context means a connection, and then disconnection, of an electrical connector. Such as those on an engine harness, behind the dash, etc. Connectors are designed for some intended life, one criteria of which is the number of times the connector can be connected/disconnected and still work properly. As with all engineering tasks, there are tradeoffs between life, cost, resistivity, surface corrosion, wire retention, etc. Connectors are almost a science unto themselves which is why they often cost so much. Unfortunately, as we see in boats, the wrong connector is used - often increasing the cost where it is unnecessary. As just one example, there is really no point in using fully waterproof connectors behind the dash... if the boat is submerged to that degree the operator has far bigger problems than whether his connectors have water in them!

[ericinmich]

Correct, by connection cycle I meant how many times the connectors can be pulled apart and reconnected. Typically that happens "never" on a production vehicle, and maybe a few times if service is needed. On the knock sensors, we have to take them off to drain the block (most applications, small block GMs) so they get cycled many more times than what was specified to the vendor of the connectors. That would be the first thing I would look for. If they are loose, then intermittent connections could fool the system into thinking there was more knock (signal comes and goes) or if it doesn't ever see any signal, then a code set for that.

[ericinmich]

That is an EXCELLENT observation. While working on some of our marine projects here (including the replacement Tige touchpad), we discovered from their spec sheets that the hyper-expensive Duetsch/Amphenol connectors are only rated for 100 connection cycles. Granted this isn't a USB charging connector on someone's cellphone, but still... if you're paying over ten bucks for the connector housing and fifty cents per machined contact, might as well drop a few more percent into giving it some longevity.

For anything used in autos, every penny counts when you sell a million a year or more of them. Take the number of connectors on a car (100s) and if each were a couple cents more, you are talking millions of dollars a year. That cost would need to be justified, ... there is a saying, do you want cheap, fast, or high quality. Pick 2.

My other favorite quote is: connectors don't

[Harbs]

Thanks folks for this info! Is it difficult to replace the knock sensors and what is the best repair manual to use? I've got a Indmar 340hp engine.

[Harbs]

Is it difficult to replace the knock sensors and how did you know it was the starboard side? I've got a 2006 22V with an Indmar engine, do you know where I could get a good repair manual for this engine?

[IDBoating]

I don't know your specific engine, but replacing knock sensors is usually a breeze. Generally they screw into the block and have a simple connector on them. Disconnect, unscrew, screw in replacement, reconnect, done.

[Harbs]

Thanks Tige Jedi, change that to Marine Power 340hp, 5.7 L GM vortec. Wonder why they disconnect these when winterizing?

[chpthril]

Thanks Tige Jedi, change that to Marine Power 340hp, 5.7 L GM vortec. Wonder why they disconnect these when winterizing?

because they are also the engine block drains. have to disconnect harness in order to thread the sensor out to drain block.