575 sci running rich
#1
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my buddy has a 42 fountain with twin 575 sci.port motor burned 20 more gallons of fuel than starboard motor.swim deck is all black on 1 side and engine loads up.any suggestions on what to look for?
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Possibly a bad coolant temp sensor ???
( ecm thinks engine is "cold", dumps more fuel)
( ecm thinks engine is "cold", dumps more fuel)
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Originally Posted by awsomethunder
they are throttle body injection,do you know what the t.p.s volts are supposed to be
CHECK the timing using the proper method too.
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I had a map sensor go bad on my 575sci last yr, was way rich at idle/part throttle but by the time I nursed it to 3500 it would drink what it was pouring in. Merc wanted 150ish, it's a GM part, 93 buick riviera 3.8 SC if I remeber right, 1/3 the price. Fixed my issue.
I'm pretty sure the tps should be .5 at idle and 4.7ish at wot, not sure what the iac count should be.
If one injector is stuck it should be obviuous watching it while idling. just remove the spark arrestor and they are in plain sight
I'm pretty sure the tps should be .5 at idle and 4.7ish at wot, not sure what the iac count should be.
If one injector is stuck it should be obviuous watching it while idling. just remove the spark arrestor and they are in plain sight
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Originally Posted by Cattitude
I'm pretty sure the tps should be .5 at idle and 4.7ish at wot, not sure what the iac count should be.
If one injector is stuck it should be obviuous watching it while idling. just remove the spark arrestor and they are in plain sight
these are the correct #s