2003 115 mercury four stroke EFI is losing power. I flushed tank 2 times, ran one tank with mercury fuel injector cleaner. changed out spark plugs (rgk lfr6A-11) changed inline fuel filter, oil filter, engine oil, lower unit gear oil. i have less than 100 hours, its on a my 22 ft sun tracker party barge. boat and engine like new, bought new in 2004. Problem: engine runs fine in driveway with hose, as soon as i put it in water, cannot increase throttle without bogging down, max speed at wide open is 16 mph, was 29-32. if i back off throttle, it levels out and runs smooth. max rpm is 3800, was 5000-5200. no leaks, no smoke, all wires and hoses fine. HELP!!!!
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Re: 2003 115 mercury efi losing power
I am a Mercury certified technician. What you need to do is take it to a Mercury dealer and have them hook it up to the computer. It sounds like the engine could be in Guardian mode or possibly a high RPM misfire. It is not something that is common and the computer program that Mercury has for those is able to test misfires and all sorts of cool stuff. It can also tell you if the engine was broke in properly, how many actual running hours are on it and even at what RPM each hour was ran. It will be able to bring up all faults that it has had in the past and any faults that are current. I know that you are probably looking for a quick, easy fix but for this problem I dont think that there is any way around taking the engine in. For what it is worth, if they charge you for more than 2 hours to run it on the computer then take it somewhere else. I can fully test the engine with the computer in about an hour. The only reason that it would take any longer is if they had to put it in the water to duplicate the problem but most shops will have a test tank that is capable of running your engine under a load at full throttle. Sorry for the bad news but I cant think of any other way and throwing new parts at it is just going to get expensive quick.
I experienced the same problem last summer. One fuel injector was blocked. Dismantle it, **** fuel backwards through the injector and open it with power from a little battery. Dirt will loosen and the injector will work again. This is not a method know by neither car nor boat workshops.
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Jun 22, 2012 - Uploaded by Brad Clark
My last test run of this motor lead me to believe I had fuel pumpissues...so in ... Mercury 9.8 h.p. 110 Outboard Motor WaterPump Repair and ...
ok no engine stated. cant help much if you can show VIN or engine name.
we can't guess the following
if carb or EFI (1988 in usa they had carbs and EFI in 1 year)
country, sorry, no country no joy, as varies by that.
why not just look, lets do this simple task.
look at engine, its a carb or just throttle body, ?
is the fuel lines to injector (s) and follow it to tank) it arrives at a filter, go past filter to tank and see a fuel pump rack in tank and 2 wires to rack and 2 to the fuel level sender, so 4 wires total that is EFI there. and is Electric pumps on all gas engines.
if carb, it can be electric or mechanical off cam. drive. same deal see that fuel line it goes to 1 or the other, if electric it has 2 wires, not its pure mechanical.
on older cars there are 2 EFI fuel lines, a loop its called.
1 is like 30psi feed line an the other is just return. 0psi.
1 example of just 2 1988 engines.
he D1 is carb (dang carbs., LOL)
the E1 is EFI.
B0563 Battery Voltage High TSM/TSSM
B1004 Fuel Level Sending Unit Low Instruments
B1005 Fuel Level Sending Unit High/Open Instruments
B1006 Accessory Line Overvoltage Instruments
B1007 Ignition Line Overvoltage Instruments
B1008 Reset Switch Closed Instruments
B1131 Alarm Output Low TSM/TSSM
B1132 Alarm Output High TSM/TSSM
B1134 Starter Output High TSM/TSSM
B1135 Accelerometer Fault TSM/TSSM
B1151 Sidecar BAS Low TSM/TSSM
B1152 Sidecar BAS High TSM/TSSM
B1153 Sidecar BAS Out of Range TSM/TSSM
P0106 MAP Sensor Rate of Range Error Carb
P0107 Map Sensor Failed Open/Low Carb
P0107 Map Sensor Open/Low EFI
P0108 Map Sensor Failed High Carb
P0108 Map Sensor High EFI
P0112 IAT Sensor Voltage Low EFI
P0113 IAT Sensor Voltage Open/High EFI
P0117 ET Sensor Voltage Low EFI
P0118 ET Sensor Voltage Open/High EFI
P0122 TP Sensor Open/Low EFI
P0123 TP Sensor High EFI
P0261 Front Injector Open/Low EFI
P0262 Front Injector High EFI
P0263 Rear Injector Open/Low EFI
P0264 Rear Injector High EFI
P0373 CKP Sensor Intermittent Carb
P0373 CKP Sensor Intermittent EFI
P0374 CKP Sensor Not Detected Carb
P0374 CKP Sensor Synch Error EFI
P0501 VSS Low Carb
P0501 VSS Low EFI
P0502 VSS High/Open Carb
P0502 VSS High/Open EFI
P0505 Loss of Idle Sped Control EFI
P0562 Battery Voltage Low Carb
P0562 Battery Voltage Low EFI
P0563 Battery Voltage High Carb
P0563 Battery Voltage High EFI
P0602 Calibration Memory Error Carb
P0603 EEPROM Failure Carb
P0603 ECM EEPROM Error EFI
P0604 RAM Failure Carb
P0605 Program Memory Error Carb
P0605 ECM Flash Error EFI
P0607 Converter Error Carb
P1001 System Relay Coil Open/Low EFI
P1002 System relay Coil High/Shorted EFI
P1003 System relay Contacts Open EFI
P1004 System Relay Contacts Closed EFI
P1009 Incorrect Password Carb
P1009 Incorrect Password EFI
P1010 Missing Password Carb
P1010 Missing Password EFI
P1351 Front Ignition Open/Low Carb
P1351 Front Ignition Open/Low EFI
P1352 Front Ignition Coil High/Shorted Carb
P1352 Front Ignition Coil High/Shorted EFI
P1353 Front Cylinder No Combustion EFI
P1354 Rear Ignition Coil Open/Low Carb
P1354 Rear Ignition Coil Open/Low EFI
P1355 Rear Ignition Coil High/Shorted Carb
P1355 Rear Ignition Coil High/Shorted EFI
P1356 Rear Cylinder No Combustion EFI
P1357 Intermittent Secondary Front EFI
P1358 Intermittent Secondary Rear EFI
U1016 Loss of ICM/ECM Serial Data Instruments
U1016 Loss of ECM Serial Data, Vehicle Speed, Vehicle Inhibit Motion or Powertrain Security Status TSM/TSSM
U1064 Loss of TSM/TSSM Serial Data Carb
U1064 Loss of TSM/TSSM Serial Data EFI
U1064 Loss of TSM/TSSM Serial Data Instruments
U1097 Loss of Speedometer Serial data Carb
U1097 Loss of Speedometer Serial data EFI
U1097 Loss of Speedometer Serial data TSM/TSSM
U1255 Missing Message at Speedometer EFI
U1255 Serial Data Error/Missing Message EFI
U1255 Serial Data Error/Missing Message Instruments
U1255 Serial Data Error/Missing Message TSM/TSSM
U1300 Serial Data Low Carb
U1300 Serial Data Low EFI
U1300 Serial Data Low Instruments
U1300 Serial Data Low TSM/TSSM
U1301 Serial Data Open/High Carb
U1301 Serial Data Open/High EFI
U1301 Serial Data Open/High Instruments
U1301 Serial Data Open/High TSM/TSSM
AFR - Air Fuel Ratio
ATS - Air Temperature Sensor
BAS - Bank Angle Sensor
CCM - Cruise Control Module
CKP - Crank Position Sensor. The CKP generates an "AC signal" which is sent to the ECM where it is used to reference engine position (TDC) and speed.
DTC - Diagnostic Trouble Codes
ECM - Electronic Control Module. (The Computer) Computes the spark advance for proper ignition timing and fuel control based on sensor inputs
(from CKP, MAP & TP sensors) and controls the low-voltage circuits for the ignition coils and injectors.
The dwell time for the ignition coil is also calculated in the microprocessor and is dependent upon battery voltage. The programmed dwell feature gives adequate spark at all speeds.
ECT - Engine Coolant Temperature. Sensor also controls the cooling fan relay that provides 12 Vdc to the fans.
EFI - Electronic Fuel Injection
EFP - Electronic Fuel Pump
ET - Engine Temperature sensor
FI - Fuel Injectors
FPR - Fuel Pressure regulator
IAC - Idle Air Control actuator
IAT - Intake Air Temperature sensor
ISS - Ion Sensing System...detonation detection
MAP - manifold Absolute Pressure sensor. The MAP sensor monitors the intake manifold pressure (vacuum) and sends the information to the ECM.
The EMC then adjusts the spark and fuel-timing advance curves for optimum performance.
TP - Throttle Position Sensor
TSM/TSSM (Turn Signal/ Turn Signal Security Module)
VE - Volume Efficiency
VSS - Vehicle Speed Sensor. Used as an input for idle speed control
Sounds like and injector problem to me. If it was a 2 stroke I'd tell you to pull the carbs and clean them ,but EFI is a whole different story. Most certaintly a fuel problem, most likely injector related, you'll most likely need to go see a marine mechanic with the proper equipment to analyze, rather than start replacing parts you may not need.