496 ho won't start
#2
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#3
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From: Rochester, NY
Constant tone alarms are for:
1.) engine coolant temp overheat,
2.) low engine oil pressure,
3.) engine overspeed,
4.) exhaust manifold cooling temp overheat
5.) sea pump PSI low FYI This is kind of common, And is said to not show up in the history. The only way to know is to watch this sensor live as it happens.
Make sure all you grounds are tight on and around the engine. And if this sensor has any paint on it it could be loosing it's ground and sounding the alarm.Or you could have picked up some air bubbels for a short time till you slowed down, Or the impeller, or impeller housing is starting to fail. This is Just a thought of what could be happening is all.Good luck with it.
Constant beep alarms are for:
1.) low outdrive lube level.
Two Alarm beeps every 60 seconds are for:
1.) Faulty cam,
2.) IAC,
3.) MAP,
4.) MAT,
5.) knock sensors.
6.) open/short in the engine cooling temp circuit
7.) open/short in fuel injector wiring circuit,
8.) open/short in oil PSI circuit,
9.) open/short in exhaust manifold cooling temp circuit, 10.) open/short in sea pump circuit,
11.) open/short in throttle position circuit
1.) engine coolant temp overheat,
2.) low engine oil pressure,
3.) engine overspeed,
4.) exhaust manifold cooling temp overheat
5.) sea pump PSI low FYI This is kind of common, And is said to not show up in the history. The only way to know is to watch this sensor live as it happens.
Make sure all you grounds are tight on and around the engine. And if this sensor has any paint on it it could be loosing it's ground and sounding the alarm.Or you could have picked up some air bubbels for a short time till you slowed down, Or the impeller, or impeller housing is starting to fail. This is Just a thought of what could be happening is all.Good luck with it.
Constant beep alarms are for:
1.) low outdrive lube level.
Two Alarm beeps every 60 seconds are for:
1.) Faulty cam,
2.) IAC,
3.) MAP,
4.) MAT,
5.) knock sensors.
6.) open/short in the engine cooling temp circuit
7.) open/short in fuel injector wiring circuit,
8.) open/short in oil PSI circuit,
9.) open/short in exhaust manifold cooling temp circuit, 10.) open/short in sea pump circuit,
11.) open/short in throttle position circuit
Last edited by Donzi ZX; 05-06-2016 at 07:26 PM.
#5
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The beeps are totally random. When the key is on it beeps all the time then stops. Then beeps on the 2 beeps every 60 second interval. It beeps the entire time you try to start it.
Impeller is brand new. Housing looked good at replacement.
Anyone know what/where the water psi sensor on it is? Is that the one that plugs into the water pump?
Impeller is brand new. Housing looked good at replacement.
Anyone know what/where the water psi sensor on it is? Is that the one that plugs into the water pump?
#6
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From: Richmond, Virginia
If there's one thing everyone on here has learned with these 496's is you have to have the PCM scanned to even begin to find the problem. You'll just be chasing your tail if you don't. Where are you located?
#8
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Joined: Jul 2011
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From: Clearwater, FL
The beeps are totally random. When the key is on it beeps all the time then stops. Then beeps on the 2 beeps every 60 second interval. It beeps the entire time you try to start it.
Impeller is brand new. Housing looked good at replacement.
Anyone know what/where the water psi sensor on it is? Is that the one that plugs into the water pump?
Impeller is brand new. Housing looked good at replacement.
Anyone know what/where the water psi sensor on it is? Is that the one that plugs into the water pump?
Lower end of the engine. Near the impeller.
Mine went bad and it took 2-3 months of chasing the issue to find it. Ended up having to use a scan tool and go cruising checking off things.
Turned out to be the water psi sensor that was like $40. Such a pain in the ass
#9
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My guess is its this or the iac. The iac is only two years old. He's having it scanned tomorrow. It's my old boat so hopefully we can get it figured out easy..
#10
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Joined: Jul 2011
Posts: 9,594
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From: Ft. Worth TX
IAC - UNLESS YOU HAVE NO tach signal if that is the case crank position sensor. Most of the time a bad crank p sensor will have no tach signal but I have seen a few times that the tach still had a signal.
If the engine every produced a fault from day one it will be in the history section of the scan - UNLESS all of that was cleared.
If the engine every produced a fault from day one it will be in the history section of the scan - UNLESS all of that was cleared.


