It could be many things. You may have a MAF sensor that can be contaminated causing these performance issues. Sometimes, if you have oil pressure problems it can affect your VVT system, such as your variable valve timing solenoid, VTC Actuator and that can cause p0300. Worse case scenario, a head gasket issue can also p0300. If you have ascan tool look at your fuel trims and see what the pcm is doing. Keep me posted.

​@@EliTheOBDTechOk!! Thank you! I'm going to check that. I'll let you know

Perhaps spark plugs as well.

When I get a chance, I'll look it up. Year, make and model?

@@EliTheOBDTech 2002 nissan altima s 2.5 liter

@@christhopherlasher2828 The knock sensor seems to be just below the exhaust manifold, bolted to the cylinder head.

@@christhopherlasher2828 my bad, after further review, it's actually on the rear of the engine. Almost next to the power steering oil pressure switch. Rear right side, almost next to the right drive shaft axle boot. The 2001 model has it beneath the exhaust manifold.

It depends on the situation. For example, if your problem is external oil leak inside the spark plug bore, then yes. In that case you have a bad spark plug seal. If your oil leak is internal causing the spark plug tip or threads to be wet with oil, then no. In that case you have either bad piston rings, bad valve stem seals or valve guides.

@@EliTheOBDTech no oil at the moment.after 3 differant valve covers and numerous oil seal kits.but running wores than ever.just changed o2 sensor and camshaft sensor.no vaccuum leaks yet

Some it's multiple issues. I'm glad you fixed your problem.

I have multiple cylinders misfire but the car runs smooth. I have 2016 altima with 420k miles. I changed the spark plight the ignition coils and the fuel injectors for 3 and 4 cylinders. Was good for 3 months then the codes came back.

@@ronniefletes92 Possibilities can be fuel delivery problem, such as weak fuel pump, dirty mass air flow sensor or vacuum leaks. I would also check for dirty throttle body.

Faulty or dirty injectors, faulty intake manifold gasket, mechanical problem. Sometimes a glitching crank sensor can cause misfire codes. Don't overlook a weak coil pack. Under heavy stress inside the cylinder it can fail. Worst case scenario, head gasket issue, without symptoms of overheating yet.

After I posted this I went to recheck that 3rd coil and found probably the smallest imperfection on it. So I switched it with the 4th one and found the code changed to p0304 so I replaced it and running better than before now. Thank you for the help in your video.

@@EliTheOBDTech I have a question too I have 03 Nissan Murano changed the spark plugs had the slightest amount of oil on one of them had a miss fire on cylinder 2 changed that now the p0300 code came up do u possibly think it’s that one coil that had a bit of oil other then that the truck runs perfectly I daily it everyday

@@juniorotero9030 Possibly. You can also swap that coil on cylinder 2 to another cylinder and drive vehicle to see if it triggers a code where you placed that coil. You can also use a spark tester the one you adjust the gap and see if the spark can jump the gap without any glitches.

You might a faulty ignition coil pack that's not firing.

You're welcome!

Hi Doreen. You can unplug the connector for each coil pack and see which one doesn't make any rpm change, that's the faulty one.

Thank you very much! 😉👍

I definitely agree with you with programming issue, not being able detect specific cylinder misfires.

So cam position sensor is failing?

It can also be a VVT issue, faulty vvt solenoid or low oil level causing valve timing issues. It could be many things, it's hard to say without being able to see scantool data.

Forgot to mention, fuel delivery issue or cam/crank sensors

Did you ever figure out what was wrong with your vehicle? Mines is doing the exact same thing.

Hi Jaqueline, have you checked your oil level? These newer cars that have VVT systems, oil level is very critical for the Variable Valve Timing to operate properly. Secondly, maybe one of your Variable Timing solenoids might me acting up/dirty filter screen. Check your oil level and let me know.

@@EliTheOBDTech I checked and oil looks good. Would the best option be the vvt?

@@jaquelinesapien1818 Not necessarily, since oil level is ok, but I wouldn't rule out a VVT problem. Another possibility would be fuel injectors being dirty/restricted or leaking. Would you by chance have a scantool? I would really like to see fuel trim data.

You will need to verify that your ignition system is working find, such as your Coil on plugs and spark plugs. Perhaps injectors, etc....

John Casey, did you resolve your issue? I'm currently experiencing this. The car has no vacuum leaks/oil leaks. Replaced, spark plugs, coils, cam sensor, valve cover gaskets, throttle body, accelerator pedal, MAF Sensor, injectors, fuel rail, o2 sensor.

Perform a relative compression sound test or compression test with a gauge to rule out a mechanical problem to that cylinder. If that's checks out good, fuel delivery to that cylinder, injector problem.

Is the check engine light on?

In Pomona, CA

Thank you eli for your quick response, cheers

Eli TheOBDTech hey I need some help

Hi there, four possible causes that come into mind: 1. Defective or worn valve guides 2. Defective piston compression rings. 3. Faulty head gasket 4. Broken piston head.

Perhaps, but it also depends if coils are coated with oil fully. A p0300 could also be triggered by a faulty crank sensor.

It can be a bad injector, harness issue or mechanical problem on cylinder 4. Let me also add, a faulty intake plenum gasket on that cylinder.

@@EliTheOBDTech well I will install new packs and plugs and hope it solves issue..thanks

​@@roadstar499 wat happened

​@@roadstar499 did it solve it

Did you get it checked out I got the code p0300 as well doesnt idle ruff I do notice sometimes it starts a little harsh tho

@@loweyes6457 i did take it this week they didn't really look at it that well but they did reset the codes and i got it home and it didn't want to restart almost immediately i gave it gas and it chug started and then it runs just fine.. i have not tried to rerun the codes because i've been busy.. but i believe the multiple misfire is gone and it's just running lean but i replaced the map sensor a year to year and a half ago.. and replace the camshaft position sensor about 3 year ago.. and i thought i did the crank shaft position sensor a year ago once the codes were popping. I believe it may have to do with pressurization of the gas tank because that's where it started giving us issues.. other than the sensors the car is basically new.. everything under the hood except for the power steering pump has been changed within a year to a year and a half, even a full suspension job has been done. I bought this car with a blown head gasket that somebody had doctored with sealant.. so even the head gasket has been replaced and the heads have been shaved and inspected

It can, but I would still check for spark with a test light to see if the component can still produce strong Kilovolts.

Moisture and spark do not get along.

What codes do you have?

@@EliTheOBDTech p0300

@@Elphxdav start with your basics, check for spark by using a test light connected to ground. Do visual inspection on your sparks plugs. Fuel delivery, perhaps dirty or restricted injectors, dirty fuel filter. A faulty intake gasket can also cause a p0300.

Forgot to mention, a faulty crank sensor can also cause a p0300.

@@EliTheOBDTech thanks

It almost sounds like a crank sensor that is glitching at moments. These sensors when they start to go bad, they tend to behave this way. Worst case scenario, maybe a fuel pump that's going bad. But it can be many things....

@@EliTheOBDTech should i start with the crank sensor or fuel pump? I bought a coil and replaced each one individually and nothing

@@nicoperez7809 Do you have a crank no start or no crank no start?

Yes it cranks it just won't turn over.

@@nicoperez7809 can you hear your fuel pump prime with ignition on?