Hello, my name is Alfred, I own a 2003 Nissan maxima 6 speed manual with 190k miles, it has been a great car overall, I bought the car with 56k miles 12 yrs ago and since I bought it, has had engine ping noise and a rattle, I ran the car like that all these years, run fine with premium chevron gasoline. I have replaced alternator twice, radiator due to plastic crap, I have replaces battery twice and the power steering high pressure hose, I have always done synthetic oil changes every 5k miles and replaced manual tranny fluid twice. two wheel bearings and a window actuator (driver side)
ISSUES: moonroof opens by itself at times. reverse lights don't work when backing up. check engine light came on and off all these years, car has always passed smog. now the car runs a bit rought, and the rattle in the engine is louder, the code is multiple misfire according to a mobile mechanic. anybodu has had these same issues with their maxima??

 

Looks like you've done a nice job taking care of your ride. At almost 200K you're probably due for new spark plugs and coils. Go to your local auto repair shop and have them read the codes to find out exactly what's wrong. The rattle could be coming from your timing chain which is a much more serious issue. Check your oil level and make sure its full.

 

I would hold off on the timing chain for now, 5.5 gens have stronger timing components than 6th gens, so guide issues are far less common.

A more common issue than a broken guide is the VIAS butterfly valve screws backing out and causing a rattle. It's a super simple fix, but I think your best bet would be to post a video with good audio quality so we can hear exactly what the problem is.

If your CEL comes and goes, that leads me to believe it's EVAP related. As mentioned above, go and get it scanned and report back with the code. My guess is P0455, but it could be a number of things.

 

Spark plugs should be swapped every 100,000 miles. That will cause rough running like you describe. Especially the misfire. Don't go cheap on the plugs. NGK Iridium plugs are great for this car. While you're in there I'd change the valve covers since they're probably leaking.

Also, clean the MAF sensor. That's cheap and easy.

These two things are the most obvious on a car this age and need to be done anyway.

As Subway said, pull the codes when the CEL comes on.

Get a mechanics stethoscope and listed around for the rattle sound. It could be anything on a car this age. https://www.harborfreight.com/mechan...ope-63296.html

The 6-MT has a mechanical switch mounted on top of it to turn on the reverse lights. If you remove the air box you'll see it on top of the transmission. Right by the mount. With the ignition, on you can pull the plug and bridge the connection to make the reverse lights come on. If they come on you know it's the switch. If not it's something else. You can pull the switch out without loosing fluid. I was able to clean the switch up by hand and it's worked ever since. If not it'll need replacing. This is assuming you've checked the fuse and bulbs.

 

Multiple misfires would indicate a vacuum leak. probably time to do the IMG

 

On the moon roof, had the same problem - seemed like a ghost because I didn't even have to hit bump. Replace the electronics around the switch and the problem was solved. Cost me about $50 in 2016. I remember it being an easy job.

On the CES light, had that often - I usually reset it using one of the OBDII reader/resetters you can buy. Car always passed smog and ran fine. I think it was probably a flaky O2 sensor or even the ECU.

I agree with the others that its time for the plugs and consider the Gen 6 valve covers as they worked for me.

Best of luck. This is a great car. Gave it to my younger son and I miss it.

 

Thank all of you for your input, I did replaced all ngk plugs, new coils and a new MAF, cleaned injectors and the service engine light went away. Still rattles and engine ping persist

 

A rattle could be nothing or precat rattle. O_O

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