Guys,

My car seems to really be losing power. Whenever I want to speed up, my auto is always downshifting. The engine seems rough. It seems like I need to tach to 4K rpm to get the acceleration I was getting at 3K.

I do regular oil changes with Mobil 1 synthetic. I've got a K+N drop in filter, I put new plugs in at 40K miles, and I always use 93 gas. Is this normal wear and tear or do you think something is wrong with my max? Is anybody else losing power at this mileage?

Matt

 

Plugs.

 

Maybe MAF going bad? Does it feel rough around a certain rpm range?

 

Gained a few pounds latetly?? Just Kidding....do you have extra weight in the car? like extra heavy items in the trunk that needs to be removed?

 

sounds like maf is dirty...its gonna fail soon!

 

Possibly the inner surfaces of the intake manifold are dirty - moisture, carbon, ambient dust and other crap. Worth a try to clean this, it's not expensive

 

Has it been particularly hot where you live? This is my first summer with my Max and it definitely loses power when it's hot out.

 

Most likley it is the heat and perhaps additional weight in the car. Run the diagnostic codes and see if anything shows up - might be a knock sensor.

 

Take the car in and have it checked out.

 

Seems like most of you think it has to do with the air intake and not the engine. I'll have the MAF sensor looked at when I take it in next time since I don't know too much about it.

I moved to FL so it is a little hotter out but it really feels sluggish. I've got nothing extra in the car, my trunk is empty. Any other ideas?

 

what kind of plugs you had put in? Were they OEM plugs? Did you gap 'em?

Guys is there a way to clean up the MAF from all that nasty smoke-like reside that is on that thin net without damaging it?

 

knock sensor

 

I put the stock NGK plugs in. I got some additional power at first but that seems to have worn off.

Where is the MAF sensor located? Should I bother messing with this?

 

Sorry I can't help you but what weight motor oil are you using?

 

5W30, maybe that's too thin?

 

If it's losing power that badly, I'd believe the MAF. Knock sensor could come into play if the engine's running too lean. (ECU reads MAF and thinks there's less air coming in than there is, and doesn't inject enough fuel) Pull the spark plugs and compare them against a chart to see if they've got blisters/signs of detonation on them.

One idea somebody proposed on another message board (nissanexa.com) was to gently move the MAF around in a bowl of rubbing alcohol. I dunno how safe this is (I doubt the film would break just gently submersing it in rubbing alcohol; spraying something on it or touching it, on the other hand, could...)

I need to examine my MAF sensor too, 'cause I don't think my Maxima is strong enough for what it should be. I mean, it's fast, but I get the feeling that it should be stronger than that. I bought it used a couple weeks ago, and I'm sure the previous owners got rid of it for a reason. Plus I heard some pinging around 1-2K RPM taking off a couple days ago (this is probably NORMAL, but a bit odd since I run premium gas all the time)

 

I may be reaching here, but what about the Cat. conveter?

 

A/T tranny! or summer heat!