I sometimes get thumps and bumps while sitting at a redlight. This only happens if i'm sitting at a light in drive. If i go into park, and sit there with the engine running, i dont have any problems. No thumps or bumps if i'm cruising along either. What could this be?

Maxima 99 SE-L

P.S: Checked ecu for codes, it came out with 0505. So that didnt help much. Any clues?

 

Uh, that noise is like coming from the pedestrian you just ran over and stop on on top of. Only the live ones cause a knocking noise.

 

Come on... seriously now

 

lol

 

This type of noise is usually due to a loose exhaust, motor, or tranny mount. Check along the length of the exhaust pipe to see if it has been rubbing. Grab ahold of it and shake in several spaces to see if it is loose. As for the engine mount, open the hood, put on e-brake, put in gear, and rev engine a little while someone is watching to see if motor moves excessively. Same for tranny.

 

Are you feeling or hearing a misfire?

 

What you described happens to me almost every day. It is fine when driving or in neutral but at a light, I can feel an occasional thund or bump. I'm thinking that one of the ignition coils that have gone bad.

 

I checked the ecu for codes and all and havent had any misfire codes. How is it supposed to sound exactly? if it's a sudden thump thump but no metal noises or anything, then it sounds like that. It can best be described as if someone near me has their bass really high and makes the car go thump thump along with the stereo.

 

i have the same problem. mine thumps/bumps one time and it seems like the engine nearly stalls (happens in a 100th/second). my guess is something with the auto tranny. the bump is pretty heavy - makes me think it's time to get rid of the car. the car drives fine when rolling.

hopefully, somebody has an answer.................