Multi cylinder misfire...

Hi, make sure that there is no intake leaks or exhaust leaks, make sure you check them good, all the best

Unplug the fuel injector wires from the injectors and do an ohm test on the 2 pins the wires clip on. I've forgotten what the reading should be, but if the injectors are bad the reading will be a bit different from the other bank. Normally when a cylinder is misfiring the injectors are not firing to shoot the fuel in. I do hope this helps, but be ready to change those injectors.

multi misfires can be from injectors --dirty and not squirting properly or low fuel pressure ---fuel pump or dirty filters
plugs are only half of a misfiring problem and the injectors are always left out
Next time include all details like make, model , year of car in your question to get a better answer

Sensor diagram for a 2000 toyota avalon and list of Pcodes

P0100 Mass or Volume Air Flow Circuit Malfunction
P0101 Mass or Volume Air Flow Circuit Range/Performance Problem
P0102 Mass or Volume Air Flow Circuit Low Input
P0103 Mass or Volume Air Flow Circuit High Input
P0104 Mass or Volume Air Flow Circuit Intermittent
P0105 Manifold Absolute Pressure/Barometric Pressure Circuit Malfunction
P0106 Manifold Absolute Pressure/Barometric Pressure Circuit Range/Performance Problem
P0107 Manifold Absolute Pressure/Barometric Pressure Circuit Low Input
P0108 Manifold Absolute Pressure/Barometric Pressure Circuit High Input
P0109 Manifold Absolute Pressure/Barometric Pressure Circuit Intermittent
P0110 Intake Air Temperature Circuit Malfunction
P0111 Intake Air Temperature Circuit Range/Performance Problem
P0112 Intake Air Temperature Circuit Low Input
P0113 Intake Air Temperature Circuit High Input
P0114 Intake Air Temperature Circuit Intermittent
P0115 Engine Coolant Temperature Circuit Malfunction
P0116 Engine Coolant Temperature Circuit Range/Performance Problem
P0117 Engine Coolant Temperature Circuit Low Input
P0118 Engine Coolant Temperature Circuit High Input
P0119 Engine Coolant Temperature Circuit Intermittent
P0120 Throttle/Pedal Position Sensor/Switch "A" Circuit Malfunction
P0121 Throttle/Pedal Position Sensor/Switch "A" Circuit Range/Performance Problem
P0122 Throttle/Pedal Position Sensor/Switch "A" Circuit Low Input
P0123 Throttle/Pedal Position Sensor/Switch "A" Circuit High Input
P0124 Throttle/Pedal Position Sensor/Switch "A" Circuit Intermittent
P0125 Insufficient Coolant Temperature For Closed Loop Fuel Control
P0126 Insufficient Coolant Temperature For Stable Operation
P0130 O2Circuit Malfunction (Bank #1 Sensor #1)
P0131 O2Sensor Circuit Low Voltage (Bank #1 Sensor #1)
P0132 O2Sensor Circuit High Voltage (Bank #1 Sensor #1)
P0133 O2Sensor Circuit Slow Response (Bank #1 Sensor #1)
P0134 O2Sensor Circuit No Activity Detected (Bank #1 Sensor #1)
P0135 O2Sensor Heater Circuit Malfunction (Bank #1 Sensor #1)
P0136 O2Sensor Circuit Malfunction (Bank #1 Sensor #2)
P0137 O2Sensor Circuit Low Voltage (Bank #1 Sensor #2)
P0138 O2Sensor Circuit High Voltage (Bank #1 Sensor #2)
P0139 O2Sensor Circuit Slow Response (Bank #1 Sensor #2)
P0140 O2Sensor Circuit No Activity Detected (Bank #1 Sensor #2)
P0141 O2Sensor Heater Circuit Malfunction (Bank #1 Sensor #2)
P0142 O2Sensor Circuit Malfunction (Bank #1 Sensor #3)
P0143 O2Sensor Circuit Low Voltage (Bank #1 Sensor #3)
P0144 O2Sensor Circuit High Voltage (Bank #1 Sensor #3)
P0145 O2Sensor Circuit Slow Response (Bank #1 Sensor #3)
P0146 O2Sensor Circuit No Activity Detected (Bank #1 Sensor #3)
P0147 O2Sensor Heater Circuit Malfunction (Bank #1 Sensor #3)
P0150 O2Sensor Circuit Malfunction (Bank #2 Sensor #1)
P0151 O2Sensor Circuit Low Voltage (Bank #2 Sensor #1)
P0152 O2Sensor Circuit High Voltage (Bank #2 Sensor #1)
P0153 O2Sensor Circuit Slow Response (Bank #2 Sensor #1)
P0154 O2Sensor Circuit No Activity Detected (Bank #2 Sensor #1)
P0155 O2Sensor Heater Circuit Malfunction (Bank #2 Sensor #1)
P0156 O2Sensor Circuit Malfunction (Bank #2 Sensor #2)
P0157 O2Sensor Circuit Low Voltage (Bank #2 Sensor #2)
P0158 O2Sensor Circuit High Voltage (Bank #2 Sensor #2)
P0159 O2Sensor Circuit Slow Response (Bank #2 Sensor #2)
P0160 O2Sensor Circuit No Activity Detected (Bank #2 Sensor #2)
P0161 O2Sensor Heater Circuit Malfunction (Bank #2 Sensor #2)
P0162 O2Sensor Circuit Malfunction (Bank #2 Sensor #3)
P0163 O2Sensor Circuit Low Voltage (Bank #2 Sensor #3)
P0164 O2Sensor Circuit High Voltage (Bank #2 Sensor #3)
P0165 O2Sensor Circuit Slow Response (Bank #2 Sensor #3)
P0166 O2Sensor Circuit No Activity Detected (Bank #2 Sensor #3)
P0167 O2Sensor Heater Circuit Malfunction (Bank #2 Sensor #3)
P0170 Fuel Trim Malfunction (Bank #1)
P0171 System Too Lean (Bank #1)
P0172 System Too Rich (Bank #1)
P0173 Fuel Trim Malfunction (Bank #2)
P0174 System Too Lean (Bank #2)
P0175 System Too Rich (Bank #2)
P0176 Fuel Composition Sensor Circuit Malfunction
P0177 Fuel Composition Sensor Circuit Range/Performance
P0178 Fuel Composition Sensor Circuit Low Input
P0179 Fuel Composition Sensor Circuit High Input
P0180 Fuel Temperature Sensor "A" Circuit Malfunction
P0181 Fuel Temperature Sensor "A" Circuit Range/Performance
P0182 Fuel Temperature Sensor "A" Circuit Low Input
P0183 Fuel Temperature Sensor "A" Circuit High Input
P0184 Fuel Temperature Sensor "A" Circuit Intermittent
P0185 Fuel Temperature Sensor "B" Circuit Malfunction
P0186 Fuel Temperature Sensor "B" Circuit Range/Performance
P0187 Fuel Temperature Sensor "B" Circuit Low Input
P0188 Fuel Temperature Sensor "B" Circuit High Input
P0189 Fuel Temperature Sensor "B" Circuit Intermittent
P0190 Fuel Rail Pressure Sensor Circuit Malfunction
P0191 Fuel Rail Pressure Sensor Circuit Range/Performance
P0192 Fuel Rail Pressure Sensor Circuit Low Input
P0193 Fuel Rail Pressure Sensor Circuit High Input
P0194 Fuel Rail Pressure Sensor Circuit Intermittent
P0195 Engine Oil Temperature Sensor Malfunction
P0196 Engine Oil Temperature Sensor Range/Performance
P0197 Engine Oil Temperature Sensor Low
P0198 Engine Oil Temperature Sensor High
P0199 Engine Oil Temperature Sensor Intermittent
P0200 Injector Circuit Malfunction
P0201 Injector Circuit Malfunction - Cylinder #1
P0202 Injector Circuit Malfunction - Cylinder #2
P0203 Injector Circuit Malfunction - Cylinder #3
P0204 Injector Circuit Malfunction - Cylinder #4
P0205 Injector Circuit Malfunction - Cylinder #5
P0206 Injector Circuit Malfunction - Cylinder #6
P0207 Injector Circuit Malfunction - Cylinder #7
P0208 Injector Circuit Malfunction - Cylinder #8
P0209 Injector Circuit Malfunction - Cylinder #9
P0210 Injector Circuit Malfunction - Cylinder #10
P0211 Injector Circuit Malfunction - Cylinder #11
P0212 Injector Circuit Malfunction - Cylinder #12
P0213 Cold Start Injector #1 Malfunction
P0214 Cold Start Injector #2 Malfunction
P0215 Engine Shutoff Solenoid Malfunction
P0216 Injection Timing Control Circuit Malfunction
P0217 Engine Over Temperature Condition
P0218 Transmission Over Temperature Condition
P0219 Engine Over Speed Condition
P0220 Throttle/Pedal Position Sensor/Switch "B" Circuit Malfunction
P0221 Throttle/Pedal Position Sensor/Switch "B" Circuit Range/Performance Problem
P0222 Throttle/Pedal Position Sensor/Switch "B" Circuit Low Input
P0223 Throttle/Pedal Position Sensor/Switch "B" Circuit High Input
P0224 Throttle/Pedal Position Sensor/Switch "B" Circuit Intermittent
P0225 Throttle/Pedal Position Sensor/Switch "C" Circuit Malfunction
P0226 Throttle/Pedal Position Sensor/Switch "C" Circuit Range/Performance Problem
P0227 Throttle/Pedal Position Sensor/Switch "C" Circuit Low Input
P0228 Throttle/Pedal Position Sensor/Switch "C" Circuit High Input
P0229 Throttle/Pedal Position Sensor/Switch "C" Circuit Intermittent
P0230 Fuel Pump Primary Circuit Malfunction
P0231 Fuel Pump Secondary Circuit Low
P0232 Fuel Pump Secondary Circuit High
P0233 Fuel Pump Secondary Circuit Intermittent
P0234 Engine Over Boost Condition
P0261 Cylinder #1 Injector Circuit Low
P0262 Cylinder #1 Injector Circuit High
P0263 Cylinder #1 Contribution/Balance Fault
P0264 Cylinder #2 Injector Circuit Low
P0265 Cylinder #2 Injector Circuit High
P0266 Cylinder #2 Contribution/Balance Fault
P0267 Cylinder #3 Injector Circuit Low
P0268 Cylinder #3 Injector Circuit High
P0269 Cylinder #3 Contribution/Balance Fault
P0270 Cylinder #4 Injector Circuit Low
P0271 Cylinder #4 Injector Circuit High
P0272 Cylinder #4 Contribution/Balance Fault
P0273 Cylinder #5 Injector Circuit Low
P0274 Cylinder #5 Injector Circuit High
P0275 Cylinder #5 Contribution/Balance Fault
P0276 Cylinder #6 Injector Circuit Low
P0277 Cylinder #6 Injector Circuit High
P0278 Cylinder #6 Contribution/Balance Fault
P0279 Cylinder #7 Injector Circuit Low
P0280 Cylinder #7 Injector Circuit High
P0281 Cylinder #7 Contribution/Balance Fault
P0282 Cylinder #8 Injector Circuit Low
P0283 Cylinder #8 Injector Circuit High
P0284 Cylinder #8 Contribution/Balance Fault
P0285 Cylinder #9 Injector Circuit Low
P0286 Cylinder #9 Injector Circuit High
P0287 Cylinder #9 Contribution/Balance Fault
P0288 Cylinder #10 Injector Circuit Low
P0289 Cylinder #10 Injector Circuit High
P0290 Cylinder #10 Contribution/Balance Fault
P0291 Cylinder #11 Injector Circuit Low
P0292 Cylinder #11 Injector Circuit High
P0293 Cylinder #11 Contribution/Balance Fault
P0294 Cylinder #12 Injector Circuit Low
P0295 Cylinder #12 Injector Circuit High
P0296 Cylinder #12 Contribution/Balance Fault
P0300 Random/Multiple Cylinder Misfire Detected
P0301 Cylinder #1 - Misfire Detected
P0302 Cylinder #2 - Misfire Detected
P0303 Cylinder #3 - Misfire Detected
P0304 Cylinder #4 - Misfire Detected
P0305 Cylinder #5 - Misfire Detected
P0306 Cylinder #6 - Misfire Detected
P0307 Cylinder #7 - Misfire Detected
P0308 Cylinder #8 - Misfire Detected
P0320 Ignition/Distributor Engine Speed Input Circuit Malfunction
P0321 Ignition/Distributor Engine Speed Input Circuit Range/Performance
P0322 Ignition/Distributor Engine Speed Input Circuit No Signal
P0323 Ignition/Distributor Engine Speed Input Circuit Intermittent
P0325 Knock Sensor #1 - Circuit Malfunction (Bank #1 or Single Sensor)
P0326 nock Sensor #1 - Circuit Range/Performance (Bank #1 or Single Sensor)
P0327 Knock Sensor #1 - Circuit Low Input (Bank #1 or Single Sensor)
P0328 Knock Sensor #1 - Circuit High Input (Bank #1 or Single Sensor)
P0329 Knock Sensor #1 - Circuit Input Intermittent (Bank #1 or Single Sensor)
P0330 Knock Sensor #2 - Circuit Malfunction (Bank #2)
P0331 Knock Sensor #2 - Circuit Range/Performance (Bank #2)
P0332 Knock Sensor #2 - Circuit Low Input (Bank #2)
P0333 Knock Sensor #2 - Circuit High Input (Bank #2)
P0334 Knock Sensor #2 - Circuit Input Intermittent (Bank #2)
P0335 Crankshaft Position Sensor "A" Circuit Malfunction
P0336 Crankshaft Position Sensor "A" Circuit Range/Performance
P0337 Crankshaft Position Sensor "A" Circuit Low Input
P0338 Crankshaft Position Sensor "A" Circuit High Input
P0339 Crankshaft Position Sensor "A" Circuit Intermittent
P0340 Camshaft Position Sensor Circuit Malfunction
P0341 Camshaft Position Sensor Circuit Range/Performance
P0342 Camshaft Position Sensor Circuit Low Input
P0343 Camshaft Position Sensor Circuit High Input
P0344 Camshaft Position Sensor Circuit Intermittent
P0350 Ignition Coil Primary/Secondary Circuit Malfunction
P0351 Ignition Coil "A" Primary/Secondary Circuit Malfunction
P0352 Ignition Coil "B" Primary/Secondary Circuit Malfunction
P0353 Ignition Coil "C" Primary/Secondary Circuit Malfunction
P0354 Ignition Coil "D" Primary/Secondary Circuit Malfunction
P0355 Ignition Coil "E" Primary/Secondary Circuit Malfunction
P0356 Ignition Coil "F" Primary/Secondary Circuit Malfunction
P0357 Ignition Coil "G" Primary/Secondary Circuit Malfunction
P0358 Ignition Coil "H" Primary/Secondary Circuit Malfunction
P0359 Ignition Coil "I" Primary/Secondary Circuit Malfunction
P0360 Ignition Coil "J" Primary/Secondary Circuit Malfunction
P0361 Ignition Coil "K" Primary/Secondary Circuit Malfunction
P0362 Ignition Coil "L" Primary/Secondary Circuit Malfunction
P0370 Timing Reference High Resolution Signal "A" Malfunction
P0371 Timing Reference High Resolution Signal "A" Too Many Pulses
P0372 Timing Reference High Resolution Signal "A" Too Few Pulses
P0373 Timing Reference High Resolution Signal "A" Intermittent/Erratic Pulses
P0374 Timing Reference High Resolution Signal "A" No Pulses
P0375 Timing Reference High Resolution Signal "B" Malfunction
P0376 Timing Reference High Resolution Signal "B" Too Many Pulses
P0377 Timing Reference High Resolution Signal "B" Too Few Pulses
P0378 Timing Reference High Resolution Signal "B" Intermittent/Erratic Pulses
P0379 Timing Reference High Resolution Signal "B" No Pulses
P0380 Glow Plug/Heater Circuit "A" Malfunction
P0381 Glow Plug/Heater Indicator Circuit Malfunction
P0382 Glow Plug/Heater Circuit "B" Malfunction
P0385 Crankshaft Position Sensor "B" Circuit Malfunction
P0386 Crankshaft Position Sensor "B" Circuit Range/Performance
P0387 Crankshaft Position Sensor "B" Circuit Low Input
P0388 Crankshaft Position Sensor "B" Circuit High Input
P0389 Crankshaft Position Sensor "B" Circuit Intermittent
P0400 Exhaust Gas Recirculation Flow Malfunction
P0401 Exhaust Gas Recirculation Flow Insufficient Detected
P0402 Exhaust Gas Recirculation Flow Excessive Detected
P0403 Exhaust Gas Recirculation Circuit Malfunction
P0404 Exhaust Gas Recirculation Circuit Range/Performance
P0405 Exhaust Gas Recirculation Sensor "A" Circuit Low
P0406 Exhaust Gas Recirculation Sensor "A" Circuit High
P0407 Exhaust Gas Recirculation Sensor "B" Circuit Low
P0408 Exhaust Gas Recirculation Sensor "B" Circuit High
P0410 Secondary Air Injection System Malfunction
P0411 Secondary Air Injection System Incorrect Flow Detected
P0412 Secondary Air Injection System Switching Valve "A" Circuit Malfunction
P0413 Secondary Air Injection System Switching Valve "A" Circuit Open
P0414 Secondary Air Injection System Switching Valve "A" Circuit Shorted
P0415 Secondary Air Injection System Switching Valve "B" Circuit Malfunction
P0416 Secondary Air Injection System Switching Valve "B" Circuit Open
P0417 Secondary Air Injection System Switching Valve "B" Circuit Shorted
P0418 Secondary Air Injection System Relay "A" Circuit Malfunction
P0419 Secondary Air Injection System Relay "B" Circuit Malfunction
P0420 Catalyst System Efficiency Below Threshold (Bank #1)
P0421 Warm Up Catalyst Efficiency Below Threshold (Bank #1)
P0422 Main Catalyst Efficiency Below Threshold (Bank #1)
P0423 Heated Catalyst Efficiency Below Threshold (Bank #1)
P0424 Heated Catalyst Temperature Below Threshold (Bank #1)
P0430 Catalyst System Efficiency Below Threshold (Bank #2)
P0431 Warm Up Catalyst Efficiency Below Threshold (Bank #2)
P0432 Main Catalyst Efficiency Below Threshold (Bank #2)
P0433 Heated Catalyst Efficiency Below Threshold (Bank #2)
P0434 Heated Catalyst Temperature Below Threshold (Bank #2)
P0440 Evaporative Emission Control System Malfunction
P0441 Evaporative Emission Control System Incorrect Purge Flow
P0442 Evaporative Emission Control System Leak Detected (Small Leak)
P0443 Evaporative Emission Control System Purge Control Valve Circuit Malfunction
P0444 Evaporative Emission Control System Purge Control Valve Circuit Open
P0445 Evaporative Emission Control System Purge Control Valve Circuit Shorted
P0446 Evaporative Emission Control System Vent Control Circuit Malfunction P0441 and/or P0446

The old give me money for nothing statement from a mechanic instead of knowing how to fix it.
code p0300 refers to random/ multiple cylinder/s misfire detected===causes--spark plug/s---HT lead/s---injector/s---ignition coil/s--low compression--wiring
code po303 refers to cylinder 3 misfire detected--- engine mechanical fault---wiring---ignition/ fuel system---injector --ECT/MAF sensor --- ECM
code p0306 refers to cylinder 6 misfire detected===causes --engine mechanical fault---wiring---ignition / fuel system---injector ---ECT/MAF sensor---ECM
code po316 refers to misfire detected during start up--first 1000 revs==causes--engine mechanical fault---wiring---ignition /fuel system---injector
code po2195 refers to heated oxygen sensor (HO2S) 1 bank 1 signal stuck lean===cayses ---HO2S---fuel pressure---injectors---intake leak
it also refers to O2S sensor 1 bank 1 same causes and also refers to HO2S 1 bank 1 implausible signal===causes --- short to positive---short to ground---Ho2S ---ECM
code po2196 refers to the same items as 2195 . some causes are also air intake restricted
Have a compression test done some where else and it will indicate the condition of the motor. The rest is sensors and wiring problems.

P0300 is multiple engine misfire detected
P0303 is misfire in cylinder 3
P0305 is misfire in cylinder 5
P0343 is camshaft position sensor A (bank 1)
P0347 is camshaft position sensor A (bank 2)
P0368 is camshaft position sensor B (bank 1)
P0392 is camshaft position sensor B (bank2)
P0496 is EVAP Canister Purge System High Purge Flow

You could have a faulty fuel injector, a bad spark plug or wire or even a bad coil. The 3.1 liters are notorious for having bad fuel injectors If there is a check engine light then you can get the code and find out which cylinder is misfiring then go from there. Or you could get the vehicle to misfire then pull of each individual injector wire to see which cylinder is misfiring, you will know which one is misfiring because when you disconnect the wire you will not feel any change at all. If you unplug one of the injectors to a cylinder that is not misfiring it will misfire much more.

P1131 -1. Misfire on bank 1
2. Vacuum leak affecting bank 1
3. Fuel injector problem bank 1

P1130 - 1. Fuel pressure high or low
2. MAP sensor dirty/defective
3. Vacuum leak on engine
4. Leaking fuel injector or fuel pressure regulator

P0300 Random Misfire Detected
P0301 Cylinder 1 Misfire Detected
P0302 Cylinder 2 Misfire Detected
P0303 Cylinder 3 Misfire Detected
according to this fault codes first mark ignition coils
3 ---------------- 6
2 ---------------- 5
1 ---------------- 4
RB-------------LB
this right banks and left bank, please remove Ignition coils with lids and spark plugs from right bank and swap with left bank, if fault code change as
P 0304 Cylinder 4 Misfire Detected
P 0305 Cylinder 5 Misfire Detected
P 0306 Cylinder 6 Misfire Detected
You can Identify it's a faulty ignition system then next swap ignition lids from ignition coils be careful each coils have two lids one short and other long bit deference and when you remove and fix it to the car keep in mind correct order because each coil two different fire for two spark plugs don't mix up, if you mix it can create the fault code.if you detect any fault ignition coils or spark plugs or lids replace that and also whether god or bad recommend to replace spark plugs, find the right that's most important thing, if this way couldn't found the any ignition fault next step is check fuel presser, when the engine running fuel presser must be around 4.5 bar without engine running must be 4 to 6 bar if the fuel presser too low need to check two different things one is fuel pump other is fuel injectors, in this case you can swap injectors from right bank to left bank and find is the injectors leaking, if not leaking faulty fuel pump.is this information helped you? if yes please leave a comment,

take sample of your fuel into clear plastic bottle from fuel line
is there any water present?
this can cause these codes and then not go on storing codes for other bank even though that bank will be missfiring also due to water & P0300 Random/Multiple Cylinder Misfire Detected being logged
check all connections to coils/leads & wiring connectors
due to miss fire codes for cyl 1,3,5 all on the same bank
also look and check for air leaks on that bank (hose knocked off or splithose)inlet manifold gasket,brake booster etc...
3 injectors being blocked slightly on same bank posible!!!
check wires and signal

was it running like this b4 tune up & repairs?
this is what codes are
P0170 Fuel Trim Malfunction (Bank 1)
P0300 Random/Multiple Cylinder Misfire Detected
P0301 Cylinder 1 Misfire Detected
P0303 Cylinder 3 Misfire Detected
P0305 Cylinder 5 Misfire Detected

the last code is for trans due to misfire/running lean on bank 1 probably a torque problem code