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502 Mag loss of power

deltaav8er

New member
"Help!!!! I have a 1993 502 Ma

"Help!!!! I have a 1993 502 Mag EFI that suddenly lost power. I was cruising at about 3000 rpm when the engine went to a very low power setting but continued to run. I found that my max rpm when in gear is about 1400 rpm, but the engine revs normally in neutral. Starting, oil temp, pressure, volts and outdrive are all normal.

Thanks
Dave."
 
"Check the fuel pressure, shou

"Check the fuel pressure, should be around 46 p.s.i. (Confirm this in your service manual) Check the spark, check the compression.

When you have done this you will know how to proceed."
 
"David
I know this sounds str


"David
I know this sounds strange but load test your engine batteries. If you have a bad battery here's what could be happening. WHen you start out the battery is hot( up to load) as you motor, the battery drops below 11 volts and the alternator is now not working and giving power so the engine will not run out to its peak output. Many A time this has been the answer. Load test your engine batteries look at the cables, check that they are tight, and clean. Good luck."
 
check cap and spark plug wires

check cap and spark plug wires i had a wire melt to my exhaust manfold once i moved it ran great it was not getting full spark like it was running on half a motor EFI could be in the computer lets hope not $$$$ to much to fix
 
when's the last time you c

when's the last time you changed the fuel filter if the motor is not getting gas it will not run high RMPS fuel pump ok ?
 
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