496 HO randomley turn off/on video
#1
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496 HO randomley turn off/on video
Any ideas what could cause it? I have scanned the computer(s). No codes beside the normal non smart craft codes. Seems like it is loosing power or something along those lines.
Normal wiggle test of the kill switch dose not result in anything.
Dealer has replaced IAC, TPS, 50 amp breakers, and $1800 ECU! One of the engines that have also replaced the fuel pump. Fuel filters are fresh.
2006 496 HO. Last scan was 370 hrs. Seems like it is looking power or something along those
Watch around 19 - 25 seconds on the video.
Some days it will do it 1 time. Other days it will do it several.
https://www.youtube.com/watch?v=YjpOWyRCmk0
Normal wiggle test of the kill switch dose not result in anything.
Dealer has replaced IAC, TPS, 50 amp breakers, and $1800 ECU! One of the engines that have also replaced the fuel pump. Fuel filters are fresh.
2006 496 HO. Last scan was 370 hrs. Seems like it is looking power or something along those
Watch around 19 - 25 seconds on the video.
Some days it will do it 1 time. Other days it will do it several.
https://www.youtube.com/watch?v=YjpOWyRCmk0
#2
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Clean, tighten and/or replace all the battery terminals.
Clean, tighten and/or replace the grounds on the back of your bell housing there is 2 on each engine bell housing.
There is an actual ground block that is on the transom, clean & tighten.
If this fails try this - run your batteries as 1 and 2 not "Both" - see what happens.
FWIW - If a dealer didnt check those things first, I would be PISSED! If you do the above, I bet you either fix or find your problem.
I know it sounds illogical but if your batteries are old and lose charge relatively quick, replace them. As soon as my last set of AGM batteries got old they did some crazy stuff.
I'm still pissed at your dealer, and you should be too!
Clean, tighten and/or replace the grounds on the back of your bell housing there is 2 on each engine bell housing.
There is an actual ground block that is on the transom, clean & tighten.
If this fails try this - run your batteries as 1 and 2 not "Both" - see what happens.
FWIW - If a dealer didnt check those things first, I would be PISSED! If you do the above, I bet you either fix or find your problem.
I know it sounds illogical but if your batteries are old and lose charge relatively quick, replace them. As soon as my last set of AGM batteries got old they did some crazy stuff.
I'm still pissed at your dealer, and you should be too!
Last edited by Keith Atlanta; 10-21-2016 at 11:44 AM.
#3
I saw (internally) broken/failing wires on the back of the key switches cause this once on a boat with 525s.
I'd also go ahead and replace the Crankshaft Position Sensor if it hasn't been done; and before you actually do that, make certain that your connector/connections to the CrankPS are all in sound condition.
BUP can confirm. The tachometer signal comes from the Crankshaft Position Sensor IIRC.
I'd also go ahead and replace the Crankshaft Position Sensor if it hasn't been done; and before you actually do that, make certain that your connector/connections to the CrankPS are all in sound condition.
BUP can confirm. The tachometer signal comes from the Crankshaft Position Sensor IIRC.
Last edited by Sydwayz; 10-21-2016 at 12:05 PM.
#5
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It appears to me no other gauges flickered/moved when the tach went to 0, is this correct ?
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#7
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Agree with Sydwayz. I had the same thing happen in my 2001 Chevy 496 equipped truck. Did it randomly for almost a year until finally crank position sensor went out completely.
#8
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Thank you guys! I do not remember if they replaced the CPS or not. Ill have Steve look it up in his paper work. This is a good boating friend's boat. He has been round and round and round with the dealer on this. So I told him I will help him out. F@#* the dealer.
Little back ground. Last time it was in for this (July) they somehow ****ed up a fuel pump and the computer.
Dropped it off for this issue Monday, they threw a few parts at it and he picked it up late Friday after they supposedly water tested it. When out the Saturday morning, both engine would not start at the dock. (boat is trailer'ed ) Back to the dealer Monday morning. One engine had a fried fuel pump (star), the other fried computer (port) IIRC .
Last edited by 92nsx; 10-21-2016 at 03:23 PM.
#9
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what I seen = No other gauge LOST power period Just the TACH - with that said if it was a connection from the batteries - back side engine grounds, cannon plug in, key switch - kill lanyard then we would see other areas losing power as well NOT just the TACH.
The tach receives its signal from the crank position sensor --- places to check first and foremost -- the crank sensor and the connection. The connection even if it has the slightest bit of moisture in it can cause problems. Check for corrosion as well and or shorted as well.
Replace the crank sensor. The NON ribbed crank sensor are way better than the older ribbed ones. You should have the NON ribbed crank sensor. But they can still go bad but not as much as the first GEN ribbed ones.
Next the tach itself can be going bad ---- then the wires to the tach and or any related as a jumper wire(s) going from the tach to whatever ---- loose or corrosion or shorted for it.
Next ignition coil(s)
Next SPARK PLUG WIRE(S) / or its boot(s) spark arc off of whatever, Also make sure all are tightly pressed down all the way to
ALSO crank sensor fault does not show all the time either.
Also lastly the cam sensor works in conjunction with the crank sensor so do not rule out the cam sensor and or its connection.
The tach receives its signal from the crank position sensor --- places to check first and foremost -- the crank sensor and the connection. The connection even if it has the slightest bit of moisture in it can cause problems. Check for corrosion as well and or shorted as well.
Replace the crank sensor. The NON ribbed crank sensor are way better than the older ribbed ones. You should have the NON ribbed crank sensor. But they can still go bad but not as much as the first GEN ribbed ones.
Next the tach itself can be going bad ---- then the wires to the tach and or any related as a jumper wire(s) going from the tach to whatever ---- loose or corrosion or shorted for it.
Next ignition coil(s)
Next SPARK PLUG WIRE(S) / or its boot(s) spark arc off of whatever, Also make sure all are tightly pressed down all the way to
ALSO crank sensor fault does not show all the time either.
Also lastly the cam sensor works in conjunction with the crank sensor so do not rule out the cam sensor and or its connection.
Last edited by BUP; 10-21-2016 at 07:24 PM.
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Any ideas what could cause it? I have scanned the computer(s). No codes beside the normal non smart craft codes. Seems like it is loosing power or something along those lines.
Normal wiggle test of the kill switch dose not result in anything.
Dealer has replaced IAC, TPS, 50 amp breakers, and $1800 ECU! One of the engines that have also replaced the fuel pump. Fuel filters are fresh.
2006 496 HO. Last scan was 370 hrs. Seems like it is looking power or something along those
Watch around 19 - 25 seconds on the video.
Some days it will do it 1 time. Other days it will do it several.
https://www.youtube.com/watch?v=YjpOWyRCmk0
Normal wiggle test of the kill switch dose not result in anything.
Dealer has replaced IAC, TPS, 50 amp breakers, and $1800 ECU! One of the engines that have also replaced the fuel pump. Fuel filters are fresh.
2006 496 HO. Last scan was 370 hrs. Seems like it is looking power or something along those
Watch around 19 - 25 seconds on the video.
Some days it will do it 1 time. Other days it will do it several.
https://www.youtube.com/watch?v=YjpOWyRCmk0