Intermittent, unpredictable engine misfires

PJ in OK

Hey Scotty! First off, huge fan of yours. I love your videos. I have a 2003 Nissan Altima with approximately 92500 miles on it (yes, that low - my grandmother rarely drove it and then gifted it to me 5 years ago). I’ve kept it in immaculate condition, fixing problems when they arise immediately. For the last month however, I’ve been experiencing intermittent, unpredictable engine misfires (totaling 5 in the last 30 days or so). I start the car and it rattles and is sluggish when I am at idle or I am accelerating slowly...but then when I give it more gas and get up to 30 or more mph, it levels out and the misfire stops, and doesn’t return. Not once during any of these misfires has my check engine light (or other light) come on. I took it in to my mechanic yesterday and based on the last time I had one (18 months ago), I requested a fuel system flush, fuel pressure test, & throttle body cleaning. While doing that I asked him to check my spark plugs and tubes to make sure they looked okay. Everything passed muster and my car noticeably had more pep after the treatment. However, this afternoon, my car misfired again (no warning lights as like before). Could I just have a bad/old tank of gas (I was away for 2 weeks and didn’t drive it, plus I haven’t driven it much since then so the original tank of gas from a month ago is now at about 1/4 a tank)? Could I not be turning the ignition switch fully (turning too quick) when I start the car, causing the misfire? With no codes appearing and no lights showing, is it strictly fuel related? I’m stumped as to what it could be. Thank you for your time & God bless!

Comments (3)
No. 1-2
PJ in OK
PJ in OK

Thanks for the reply! The error code lead to my throttle body. I've posted a new question regarding that minutes ago.

Scotty Kilmer
Scotty Kilmer

Editor

Change the fuel filter in pressure test a fuel pump pray it's that and not the head gasket blowing which those engines are known for