Misfires and flashing CEL

[ecp]

Originally Posted by blue62

Those O2 sensors should be 4 wire sensors.
On a 4 wire look for two wires of the same color they are the heater circuit.
They should show 12v with key on.
Of the other two one is ground.
The other one is the signal wire back to the DME/ECU
Hope that helps.

I have gone back and re- read your posts in this thread.
In post #12 you stated that the O2 sensor voltage was .04
In post #13 you state it is reading nothing.
In post # 15 you state there is no signal but the voltage is close to .0v
Seems that the bank 2 sensor is working.

These O2 sensors work in a very very narrow range.
You stated you have not gotten any O2 sensor codes so my guess (after re reading your posts) is that the wiring is fine.
You could back prob the harness to sensor connection from the sensor side of the connection and check the two wires that are the same color. you should get 12v or near battery voltage with key on.
If that circuit (heater circuit) is good I would bet that the wiring is good. But that Cyl. may be dead as you stated.

If you think you have a dead Cyl. you can check it with a compression gauge.
Or use a vacuum gauge hooked up to the intake.
The needle will tick every time the dead cyl. comes up on the compression stroke.
Compression gauge will be easier if your not familiar with reading vacuum gauge needle action.

Or as JFP stated water on the exhaust for that cyl.

Got it running. it’s cylinders one and two that are dead. confirmed with water trick. o2 sensors reading normal. p0303 gone. all i’m left with is p0300, p0301, p0302.

could it possibly be spark or injector wiring? i don’t know how two cylinders would die at the same time.

[blue62]

Originally Posted by ecp

Got it running. it’s cylinders one and two that are dead. confirmed with water trick. o2 sensors reading normal. p0303 gone. all i’m left with is p0300, p0301, p0302.

could it possibly be spark or injector wiring? i don’t know how two cylinders would die at the same time.

you could use a Digital volt meter at the injector to see if you getting voltage with engine running. Or do the same at the coils.
Once you know which is the issue you can start to trouble shoot the wiring.
You could pull the fuel pump relay and just crank the motor.
BUT you want to make sure that relay does not also supply injector voltage.

Or do a simple compression test at those two cyl. just to make sure the direction to go.

Mice love to chew wires for some reason could be vermon chewed the wiring.

[ecp]

Originally Posted by blue62

you could use a Digital volt meter at the injector to see if you getting voltage with engine running. Or do the same at the coils.
Once you know which is the issue you can start to trouble shoot the wiring.
You could pull the fuel pump relay and just crank the motor.
BUT you want to make sure that relay does not also supply injector voltage.

Or do a simple compression test at those two cyl. just to make sure the direction to go.

Mice love to chew wires for some reason could be vermon chewed the wiring.

I’ll run a compression test tomorrow if poking around with the wiring doesn’t fan out. which terminals should i be testing on the coil for voltage. and i’m assuming i should be getting 12v on the coil and somewhere around 5v for injectors?