For a while my 03 AT maxima has been making a subtle thump or chunk sound when I am pulled up to a stop light. It is more than a sound, it feels like someone is bumping my car with theirs from the front VERY lightly. My car idles at about 300 rpm and the tach does not change when the thump happens. It is randomly timed between 5 and 15 seconds. I have not noticed a difference between when the car is cold or warmed up. This event occurs in both Drive, 1, 2 and Reverse. If i increase the throttle by even 1 or two lines (100/200rmp) the problem does not happen at all. The "kick" is in a backward direction. I figured this out by very slowly releasing my brake pedal until the car JUST started to inch forward, when the kick happens my car hesitated in its crawl for the instant of the malfunction. Event does not seem to depend on quality of gas in tank.

ANY IDEAS?

Thank you for taking the time to read this

 

check for ATF condition and level.

 

Ill check the level, but i had it fully flushed about a year ago. Thanks for your input

 

Aren't you misreading your tach? 300 RPM is way too low to start with. Even with a load on the engine (in gear) the idle should be more like about 600 RPM. What's the idle RPM in N or P? With the engine warmed up it should be 675+/-50 RPM. When you select a gear the idle speed will drop momentarily, but it should recover. If you put it in gear after a "cold start" when the idle speed is around 1200 RPM, let's say, any weird noises? Your thumping/"hesitation" when sitting/crawling in D, could be the result of low tranny oil pump output, if your idle is as low as you seem to be suggesting.

 

You are correct, i misread the tach below the 1000 rpm it was a different scale, well it starts at 500. My idle is in the correct thresh-hold for each said event/status and rebounds properly. My car doesnt make any funny noises when first put in gear on a cold start except if the car is on a slight grade. (yes i do use my parking brake)

I checked my at fluid when the car was hot and its still really red, however it looked like it was high, like way high, i took the dipstick out several times and wiped it off and put it back in and it came out high ever time. Is it something that should only be read when the car is cold?

So i guess i am back to ground zero.

 

I thought that you might have misread the tach.......I don't think the engine will continue to run at 300 RPM. Are you checking the fluid with the engine/tranny fully warmed up with the engine idling in P and on level ground? If you check it with the engine shutdown, it will read way high.

 

Aparently i am a rookie beotch with many things to learn. I read it when the car was parked, level but off. Im guessing its probably fine, ill check soon. Thank you for your wisdom. I guess i have to hope to hear from someone else who has the same problem considering its so obscure?

 

sounds like a rough idle that only get corrected when the car is slightly moving. I'd say coils going bad? throttle body dirty? MAF dirty? I had a similar problem but is slowly got worst and i think mine are coils, one is just going bad. Under non brake and acceleration i dont feel it, but once in a while at a light it sputters.