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Roy Belding
Roy Belding, ASE Certified Technician
Category: Nissan
Satisfied Customers: 5870
Experience:  41 years expierence on all cars and trucks to 2014
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2005 Nissan frontier, P0300 code, multiple misfires I have

Customer Question

Customer: ***** *****, 2005 Nissan frontier, P0300 code, multiple misfires I have changes the plugs, and checked air filter, it only happens once the vehicle is warmed up
JA: Thanks. Can you give me any more details about your issue?
Customer: what would you like? once it warms up, the check engine light starts flashing, I plug in my code tester and reads "multiple misfire" in an effort to clear them I changed out plugs, and cleaned all coils and changed the air filter, next will be Mass AF sensor cleaning, once it warms up it flashes and looses power
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Submitted: 1 year ago.
Category: Nissan
Expert:  Roy Belding replied 1 year ago.

good evening my name is ***** ***** I will assist

did you change any coils?? what were the codes for the cylinders????? was 300 the only code???


Customer: replied 1 year ago.
did not change the coils, and there was only the 300 code, indicated multiple misfires.
Expert:  Roy Belding replied 1 year ago.

ok, did you have the check engine light flashing???

do you have a scan tool that can read miss fire data??


Customer: replied 1 year ago.
there is no additional numbers listed, the only other thing that shows up on my odb reader is O2 sensor 2 error. the Service light will come on after warmed up and flash as long as you are trying to accelerate, it then goes steady once the vehicle is just at a maintained speed. Any additional gas applied will result in the light flashing again. No my CENTEC until does not show individual cylinder information.
I just ordered a new O2 sensor and will replace that tuesday / wed when it comes in
Expert:  Roy Belding replied 1 year ago.

ok, the sensor is not the source of the issue.

it sounds like there is a secondary break down and causing a miss fire. it sounds like a coil has failed. I would remove the coils and inspect the boots for any white marks along the boot. that would indicate electrical leakage and would eplain the miss fire under load.


Customer: replied 1 year ago.
nothing on the coils, no electrical burns or residue. Wondering if the drivers side cat is plugged up.
Expert:  Roy Belding replied 1 year ago.

I think your issue is still between the coils, plugs or injectors being clogged. if you had a plugged cat, you would have trouble with rpm being limited, no power.


Customer: replied 1 year ago.
There is no power, I mentioned that as one of the symptoms, its a struggle to get above 50 and as soon as you try to it starts the flashing SEL. The lower cat was considerably warmer than the pipe behind the cat.
Expert:  Roy Belding replied 1 year ago.

ok, I would unbolt the cat and see if it is any better. that will allow the engine to breather better. that will alos tell us if the cat is clogged