Need Help - Merc. 350 Alarm on when engine on.
#1
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I bought a (beat) 2001 Formula 292 FasTech w/350s and Bravo 1s.
I fixed all the issues I could find, and it does run (or did last season).
Over the winter I discovered the engine alarms were cut.
I repaired the wiring, and found the one engine w/an alarm state.
I turn the key to run, get 2 beeps, then silence.
I start the engine, and within a few seconds, I get a constant beep, until I shut the engine off.
I unplugged the drive lube bottle wiring - no effect
Unplugged the oil pressure switch - no effect
Replaced the ECT sensor - no effect.
STRB engine Serial Number: 0M047350
I don't know what else to check before buying a scan tool. Engine seems to have 100% power level. (Within 200 RPM of port at WOT).
Thanks for any help. I've been over the service manual top to bottom, but am hoping for a fix that doesn't mean buying a $550 scan tool...
I fixed all the issues I could find, and it does run (or did last season).
Over the winter I discovered the engine alarms were cut.
I repaired the wiring, and found the one engine w/an alarm state.
I turn the key to run, get 2 beeps, then silence.
I start the engine, and within a few seconds, I get a constant beep, until I shut the engine off.
I unplugged the drive lube bottle wiring - no effect
Unplugged the oil pressure switch - no effect
Replaced the ECT sensor - no effect.
STRB engine Serial Number: 0M047350
I don't know what else to check before buying a scan tool. Engine seems to have 100% power level. (Within 200 RPM of port at WOT).
Thanks for any help. I've been over the service manual top to bottom, but am hoping for a fix that doesn't mean buying a $550 scan tool...
#2
Charter Member # 55
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Have it scanned or buy a scanner or here is a cheat Make a Marine EFI code tool for less than $1.00
Throwing parts at it without knowing the problem is waste of $$$.
Throwing parts at it without knowing the problem is waste of $$$.
#3
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this is a MEFI 3 going off the top of my head
Prob a scan might show a general warning fault - innwhich is the oil pressure. IMO the oil pressure switch is bad or wired incorrectly ??? and or its sender
other possible issues could be coolant temp switch / sender and or its wiring. Also the correct gaskets are needed for the T stat as that can in some cases cause issues. IMO it might be best to have your app looked at by someone whom is OEM trained. If your in Texas --- North Texas especially is where I am located if that someone ever needed to look at it.
Yes 550 bucks for a scan tool --- to maybe even not tell you anything . MEFI 3 and its scan will only show 17 possible fault codes and many times will not show any fault codes or even shows multiple fault codes .
Not having eyes on the app - possible could be --- bad and or incorrect wiring - possible wiring harness issues ??? cutting the warning horns out of the mix was done by a do it yourselfer HACK 4 sure
Prob a scan might show a general warning fault - innwhich is the oil pressure. IMO the oil pressure switch is bad or wired incorrectly ??? and or its sender
other possible issues could be coolant temp switch / sender and or its wiring. Also the correct gaskets are needed for the T stat as that can in some cases cause issues. IMO it might be best to have your app looked at by someone whom is OEM trained. If your in Texas --- North Texas especially is where I am located if that someone ever needed to look at it.
Yes 550 bucks for a scan tool --- to maybe even not tell you anything . MEFI 3 and its scan will only show 17 possible fault codes and many times will not show any fault codes or even shows multiple fault codes .
Not having eyes on the app - possible could be --- bad and or incorrect wiring - possible wiring harness issues ??? cutting the warning horns out of the mix was done by a do it yourselfer HACK 4 sure
Last edited by BUP; 04-21-2018 at 01:32 PM.
#4
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Thread Starter
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Have it scanned or buy a scanner or here is a cheat Make a Marine EFI code tool for less than $1.00
Throwing parts at it without knowing the problem is waste of $$$.
Throwing parts at it without knowing the problem is waste of $$$.
Yes, it's a MEFI 3
thanks again, shame radio shack went under, now I'll have to check walmart for a LED and supplies...
#5
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It worked great!
I got 2 codes
ECT Sensor too cold
Air Intake Manifold sensor too cold.
I'm replacing both, clearing the codes, then giving it a go...
I got 2 codes
ECT Sensor too cold
Air Intake Manifold sensor too cold.
I'm replacing both, clearing the codes, then giving it a go...