Multiple Cylinder Misfire 02 Nissan Maxima
So I had a weird issue with my 02 Maxima. Engine light would flash when at red light but stops after driving for a few seconds. Also, when I turn on the A/C, the check engine stops flashing. I had the multiple cylinder misfire P0300 code which led to me changing the following: two catalytic converters front and back, valve cover gaskets front and back, spark plugs, and coils. This temporarily fixed the issue until recently, the same flashing check engine light is occurring again. I am at my wits end and definitely cannot afford to buy another car at the moment. Any tips or idea what could be causing this issue? Side note: sometimes the car idle smooth with no issues and sometimes, the idle is slightly not smooth which causes the check engine to start flashing.
Wow! Those were notorious for having bad ignition coils. I would replace all of them and see what happens first. You've already done some obvious stuff but the coils are annoying problem with that vehicle
I have replaced all of the coils less than 3 months ago
Did you use OEM coils or aftermarket? Aftermarket Chinese coils usually last 2-3 months and then you’re back to square one.
Is there a way to increase the idle to say 1k?
You'd have to look up the specifications on your car but in my experience most modern 4 and 6 cylinder engines are set up to idle at around 900-1000 rpm. If your rpm is dropping as low as 400 that's a problem. I am not familiar with your fuel injection system but cleaning the IAC valve and throttle body would probably good places to start.
I am honestly not sure.
Then have the vehicle diagnosed by a professional mechanic. You can then decide if you want to perform the repair yourself, or let the mechanic do all the work.
Did you perform the work @chucktobias suggested? -