05 maxima car running rough

[84johnv]

I have an 05 maxima. When I step on the gas paddle the car would shake and raddled? Don't know what's wrong with it. Please help much appreciated

[maxhopper]

How many miles? When were the spark plugs last replaced?

[84johnv]

I just replace all 6 spark plugs and the car still runs rough when I step on the gas paddle. By the way, I'm from canada so we go by kilometre 160,000. Also I replace all 3 coils in the back as well. engine light came on and it says "service engine soon". I have no idea what's wrong with it now? Thanks for the reply. Any ideas would be much appreciated

[84johnv]

I plug OBD2 scanner in and it read P0300 multiple misfire. I just check all the coil and every coil is in good working condition. I don't seem to know what is wrong with it. Any body have any advice??

[maxhopper]

Did you use NGK platinum plugs?

[84johnv]

Yes I did use NGK spark plugs. Today I'm checking maf sensor and cleaning it to see if that we'll help the problem.. Thanks for the advice much appreciated. We'll keep you on an update on the problem. Again thanks you for the reply

[84johnv]

Checked the maf and everything is in perfect working order. The car idles fine, but when i step on the gas pedal the car shakes and looses power. Still the same reading multiple misfire . Any input about this problem well help alot. Thank you

[84johnv]

Finally found the problem of p0300. I went to diagnosed at a near by mechanic shop and the scanner put out a code P0301. So the misfire was in cylinder 1 and I found out it was the injector. I took it out and have the same mechanic shop serviced it. Now the car is running at 100%. With the new coils and plugs, the car is performing at its best. Hope this help the next person with the same problem.. Thank you