P0300 and P0304 Nissan Altima 2.5

Question

I am having a problem with my 2.5 Nissan Altima I have changed the battery spark plugs cylinders ignition coils starter fuel pump fuel injectors fuel injectors and first I was having a cold a P0300 Only now I have a P0304 code the car runs Immaculate is just when you turn her on she has hesitation trouble starting, a little bit. I also noticed that when the AC is on and not off as she is being turned on she also has hesitation in addition I am constantly putting in coolant about every week although there is no leaks what can be the problem I love my Nissan and I do not want to get rid of her as she runs immaculate any suggestions? And I almost forgot I also changed the crank sensors.

Answer 1

HI there

Check the head gasket for leaking coolant into the #4 cylinder. To do this, pressure test the cooling system for about an hour, then remove the plug and coil on #4. Take a flashlight and look into the cylinder. You will likely see a puddle of coolant on top of the piston. It's a very common issue, and you have all the symptoms.

Comments

Last night she failed to start i changed the 4th coil again and i moved teased wires connected a bit then i moved battery and it started. I do see moisture and i do put coolant constantly. I ordered the head gasket i hope it lasts until then. My new fuel pump was making humming sounds and i am replacing it today. I hear loud sucking noise from it. Ugh anything else you can think of i really need my car for my client im so ready to give up and finance a car =(

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Sorry for the bad news, I know it's the head gasket causing the misfire and the starting issue. It's a very common problem on this engine in these cars. Best of luck, i am sure the head gasket will resolve the problem for you though.

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Ok i will make sure i put that in as soon as it arrives thank you. Ill stay in contact. I appriciate your time

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I just checked the head gasket and it turned from blue to green. So my head gasket is blown. I do hope this problem gets resolved. Thank youbso much for pointing that out ill let you know how everything turns out.

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I did the gasket and the p0300 is gone. However, now my car when i was driving at normal speed and stopped at stop sign and accelerated it did not go passed 20mph. The power was running normal just not the acceleration rpms were down to my mechanic thinks is the throttle the car is 10 years old and who knows if they ever changed it... what do you think.... the idling to was ok just not the acceleration. Before all of this happened i was at walgreens and when i turned my car on the battery and break light was on so i shut the car off and turned on and the light went away. Also, i did the same thing i restared the car and car picked up normal speed. Help me please you were right about the first thing. So im sure you can possibly figure this one out.