HAVE LOW POWER OUTPUT ON MY 2Y FOUR CYLINDER ENGINE WITH A CARBURATOR

The Peugeot 504 XS produced in 1994 came with a range of engine options, including a 2.0-liter inline-four gasoline engine with a maximum power output of 120 horsepower (88 kW) and a 2.3-liter inline-four diesel engine with a maximum power output of 71 horsepower (52 kW). It's important to note that the engine power may vary depending on the specific model and region where the car was sold.

.....hi, according to the manual three stages starting off at 30 Nm then 60 Nm, finishing with 88 Nm. Do you have new head bolts and always start at the middle of the cylinder head working your way outwards towards either end.
Remember most head gasket failures are due to dirty surfaces or warped cylinder heads.

It should be in this manual

http://olybrake.com/pdf/fel_pro_torque_specs_guide.pdf

A four-cylinder engine has four spark plugs. An important part of the power-generating process, each spark plug is responsible for igniting the fuel and air mixture inside of its cylinder. At the beginning of a stroke, a piston moves downward in its cylinder, drawing in a precise mixture of gas and air. After reaching the bottom, the piston moves back up, heavily compressing the mixture. Once it reaches the top, the spark plug ignites the mixture, and the explosion forces the piston down into the cylinder. This mechanical movement is harnessed and used to power the vehicle. Some large engines may have two spark plugs per cylinder to ensure that complete combustion is achieved and maximum power is generated.

Timing is off or valve is sticking. You have compression coming out of the intake. Do an engine compression test, if any cylinder is below 90 that one has a valve problem. If all cylinders are low, timing chain is off or other big problem.

Is it a 4 cylinder engine, and all four cylinders are misfiring?

Misfires will set a code when the computer senses a lag in power output from a cylinder, based on the input from the crank position sensor. Misfires are usually caused from a loss or a problem with gas, spark, or compression-one of those three is wrong for a misfire to occur. New coils and plugs, so probably not a spark problem-unless the spark timing is wrong-let's leave that for now. You should have the fuel pressure tested, and see if pressure is as specified. If pressure is low, and you have new filter, probably a weak pump.

Check cylinder compression as a last resort. Your lowest reading cylinder should be within 75% of the highest reading cylinder. A compression test is a good indicator of the internal health of the engine, the higher the compression, the more power output from that cylinder. But it should be even and balanced, lowest should be within 75% of the highest reading.

So, gas, spark, or compression?

The Nissan FD42 is a 4.2 l (4,212 cc, 257.03 cu·in) straight-four, water-cooled naturally aspirated diesel engine from Nissan FD family. The engine was manufactured by UD Trucks (Nissan Diesel) from 1991 to 1995.
The Nissan FD42 has a cast-iron cylinder block, a cylinder head with OHV (overhead valves with single camshaft), two valves per cylinder (8 in total) and a direct fuel injection system.
The cylinder bore is 108.0 mm (4.25 in) and the piston stroke is 115.0 mm (4.53 in), and the compression ratio rating is 18.0:1. The Nissan FD42 engine produced 125 PS (92 kW; 123 HP) at 3,200 rpm of maximum output power and 299 N·m (30.5 kg·m, 220.4 ft·lb) at 2,000 rpm of peak torque.
https://www.breathervalve.net

lost engine power
well, which engine.?????? which I4 , which V6?
what country>> diff, engines (and fueling ) sold in diffr, countries.
so..................??????????????
Gen 5 hilux
one of these?
1.8 L 2Y-U I4
2.4 L 22R-E I4
3.0 L 3VZ-E V6
2.4 L 2L diesel I4
2.8 L 3L diesel I4

some countries ran carbs then.
which engine,
is it fuel injected , EFI? (-E is EF)

now the Generic answer.
1: low compression on all or 1 cylinders.
2: bad spark or timed wrong, (gas engines)
3: wrong fuel rates, (too much or too little)
too much is misfire, too little is bog.
on diesel too much is black cloud.
too little bogs.
there is a simple test for each, path.

Hello, It should actually be an oil sending unit, and is located on the back of the intake manifold to the left of the distributor. *The P0523 is Oil Pressure Sending Unit Voltage too high *P1693 Generic fault indicating a fault in the bus or PCM/ECM interface *P1682 - I can't find this code Anyways, I will post here all the error codes for future reference. Dodge Cummins Check Engine Error Codes Cycle Key on-off-on-off-on to read codes in odometer display P0002 ECM fuel calibration error P0016 Crankshaft/Camshaft Timing Misalignment/Out-of- Sync P0071 Ambient Temperature Sensor Performance / Rationality P0072 Ambient Temperature Sensor Low P0073 Ambient Temperature Sensor High P0088 Fuel Rail Pressure Too High P0106 Manifold Absolute Pressure Sensor Performance / Rationality P0107 Manifold Absolute Pressure Sensor Low P0108 Manifold Absolute Pressure Sensor High P0111 Intake Air / Charge Temperature Sensor Performance / Rationality P0112 Intake Air / Charge Temperature Sensor Low P0113 Intake Air / Charge Temperature Sensor High P0116 Engine Coolant Temperature Sensor Performance / Rationality P0117 Engine Coolant Temperature Sensor Low P0118 Engine Coolant Temperature Sensor High P0121 Accelerator Position Sensor (APPS) Signal Voltage Too Low P0122 Accelerator Position Sensor (APPS) LowAPPS Voltage Input Too Low P0123 Accelerator Position Sensor (APPS) Signal Voltage Too High P0128 Cooling System Error / Thermostat Rationality P0148 Fuel Delivery Error P0168 Fuel Temp Too High P0169 Water-in-Fuel Detected For Too Long P0192 Fuel Rail Pressure Sensor Low P0193 Fuel Rail Pressure Sensor High P0201 Fuel Injector 1 Circuit P0202 Fuel Injector 2 Circuit P0203 Fuel Injector 3 Circuit P0204 Fuel Injector 4 Circuit P0205 Fuel Injector 5 Circuit P0206 Fuel Injector 6 Circuit P0216 Fuel Injection pump Timing Malfunciton [new injector pump time] P0217 Coolant Temperature Too High P0219 Engine Overspeed P0230 Transfer pump circuit out of range P0234 Turbocharger Overboost Condition P0235 Turbocharger Boost Sensor A Circuit P0236 Turbocharger Boost Pressure Sensor Performance / Rationality P0237 Turbocharger Boost Pressure Sensor Low P0238 Turbocharger Boost Pressure Sensor High P0251 Fuel Injection Pump Mechanical Failure Fuel Valve Feedback Circuit P0252 Injection Pump Fuel Metering Control "A" Range/Performance P0253 Fuel Injection Pump Fuel Valve Open Circuit P0254 Fuel Injection Pump Fuel Valve Current Too High P0300 Multiple Cylinder Misfire P0301 Cylinder 1 Misfire P0302 Cylinder 2 Misfire P0303 Cylinder 3 Misfire P0304 Cylinder 4 Misfire P0305 Cylinder 5 Misfire P0306 Cylinder 6 Misfire P0335 Crankshaft Position Sensor Circuit P0336 Crankshaft Position Sensor Performance P0337 Crankshaft Position Sensor Circuit Low P0338 Crankshaft Position Sensor Circuit High P0340 Camshaft Position Sensor Circuit P0341 Camshaft Position Sensor Performance / Rationality P0370 Timing Reference High Resolution Signal "A" P0380 Intake Air Heater #1 Control circuit P0381 Wait-to-Start Lamp Inoperative P0382 Intake Air Heater #2 Control circuit P0460 Fuel Level Sensor A Circuit P0461 Fuel Level Sensor 1 Performance / Rationality P0462 Fuel Level Sensor 1 Low P0463 Fuel Level Sensor 1 High P0477 Exhaust Pressure Control Relay Low P0478 Exhaust Pressure Control Relay High P0480 Cooling Fan 1 Control Circuit/Open (Low Speed Fan Relay) P0483 Cooling Fan Speed P0500 Vehicle Speed Sensor 1 Circuit, or No Vehicle Speed Reference Signal 1 P0514 Battery Temperature Sensor Performance / Rationality P0516 Battery Temperature Sensor Low P0517 Battery Temperature Sensor High P0521 Oil Pressure Sensor Performance / Rationality P0522 Engine Oil Pressure Sensor/Switch Circuit Low Input P0523 Oil Pressure Sending Unit Voltage too high P0524 Oil Pressure Too Low P0532 A/C Pressure Sensor Low P0533 A/C Pressure Sensor High P0541 Intake Air Heater Relay 1 Low P0542 Intake Air Heater Relay 1 High P0562 Battery Voltage Low P0563 Battery Voltage High P0572 Brake Switch 1 Low P0573 Brake Switch 1 High P0576 Cruise Control Input Circuit Low P0580 Speed Control Multiplexed Switch 1 Low P0581 Speed Control Multiplexed Switch 1 High P0602 Control Module Programming Error/NotProgrammed P0604 Internal Control Module RAM Integrity Failure P0606 Internal ECM Processor P0607 ECU Internal Performance P0622 Generator Field Control Circuit P0628 Fuel Pump Relay Circuit Low, or Fuel Lift Pump Control Circuit Low P0629 Fuel Pump Relay Circuit High, or Fuel Lift Pump Control Circuit High P0630 VIN Not Programmed in PCM P0633 SKIM Key Not Programmed in PCM P0642 Sensor Reference Voltage 1 Circuit Low P0643 Sensor Reference Voltage 1 Circuit High P0646 A/C Clutch Relay Circuit Low P0647 A/C Clutch Relay Circuit High P0652 Sensor Reference Voltage 2 Circuit Low P0653 Sensor Reference Voltage 2 Circuit High P0698 Sensor Reference Voltage 3 Circuit Low P0699 Sensor Reference Voltage 3 Circuit High P0700 Transmission Control System (MIL Request) P0743 Torque Converter Clutch Circuit Electrical P0753 Shift Solenoid "A" Electrical P0837 Four Wheel Drive (4WD) Switch Performance / Rationality P0838 Four Wheel Drive (4WD) Switch Circuit Low P0839 Four Wheel Drive (4WD) Switch Circuit High P1488 Auxiliary 5 volt supply output is too low P1492 Ambient/batt temp sensor volts too high P1493 Ambient/batt temp sensor volts too low P1596 Speed Control Switch always high P1597 Speed Control Switch always low P1652 J1850 Communication Bus P1687 No Cluster BUS Message or No Messages from the Mechanical Instrument Cluster P1688 Internal Fuel Injection Pump Controller Failure P1689 No Communication Between ECM & Injection Pump Module P1690 Fuel injection pump CKP Sensor Does Not Agree With ECM CKP Sensor P1691 Fuel Injection Pump Controller Calibration Failure P1693 Generic fault indicating a fault in the bus or PCM/ECM interface P1757 Governor pressure is above 3 PSI when 0 PSI is requested P1762 Governor Press Sensor Offset Volts Too Low or Too High P1765 Transmission 12 volt supply relay control circuit P2121 Pedal Position Sensor 1 Performance / Rationality P2122 Pedal Position Sensor 1 Low P2123 Pedal Position Sensor 1 High P2127 Pedal Validation Switch 2 Low P2128 Pedal Validation Switch 2 High P2146 Fuel Injector Group 1 Supply Voltage Circuit P2149 Fuel Injector Group 2 Supply Voltage Circuit P2266 Water in Fuel Sensor Circuit Low P2269 Water in Fuel Condition P2502 Charging System Output Voltage P2503 Charging System Output Low P2504 Charging System Output High P2509 ECM/PCM Power Input Signal Intermittent P2607 Intake Air Heater Relay 2 Low P2608 Intake Air Heater Relay 2 High P2609 Intake Air Heater System Performance Hope this will help you. Cheers! Ryan