knock on startup

Daishi · 01-13-2010, 06:38 PM

Quote:

Originally Posted by sminky63

Mine did the same thing...9 degree tempurature outside. Even with a warm engine, it made this disturding knocking sound on start up. Now that the temp outside is higher, the car hasn't done it again. I think (and hope) that it's just an extreme cold temp thing.

I think that the 370Z just doesn't like really cold weather.

agreed the car hates the cold weather.. now my intelligent key warning light comes on occasionally and my steering wheel isnt locking. hopefully its just cuz its really cold out.. id notice in the morning when its 20 degrees out id go to start the car and the mechanism that unlocks the wheel would take longer than normal to unlock.

spearfish25 · 01-15-2010, 08:39 AM

Quote:

Originally Posted by Daishi

agreed the car hates the cold weather.. now my intelligent key warning light comes on occasionally and my steering wheel isnt locking. hopefully its just cuz its really cold out.. id notice in the morning when its 20 degrees out id go to start the car and the mechanism that unlocks the wheel would take longer than normal to unlock.

Nissan probably screwed up your car when they changed the starter.

Rereading your OP, I have noticed the same thing a couple times with my car. If I drive home from work (engine warm), turn off the engine, and then immediately restart it (eg if I don't like how far I've pulled into a space and need to move the car), there is a <1sec knock when it restarts.

My guess is the A/F ratio is 'off' with such a quick restart and the car/ECU quickly fixes the issue. I don't know if it's residual fuel, time needed for the injectors to reset and start working, etc.

I NEVER get a knock when I cold start the car or wait a few minutes before restarting.

hsdw · 12-14-2010, 10:11 PM

Hi there,

I recently bought a 370Z with the 7 speed auto. It is cold here where I'm from.
-6F. Car has about 2100 miles and I noticed the same knocking noise on start up after the car has been warmed up. I would restart the car within a minute and get this knocking sound sort of like a diesel engine for about 1 second.

Any update on this situation? Is this a problem and it is NOT normal?

Thanks.

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12-14-2010, 10:11 PM	#3 (permalink)
hsdw Base Member Join Date: Dec 2010 Location: Canada Posts: 5 Drives: 370Z Rep Power: 15	Hi there, I recently bought a 370Z with the 7 speed auto. It is cold here where I'm from. -6F. Car has about 2100 miles and I noticed the same knocking noise on start up after the car has been warmed up. I would restart the car within a minute and get this knocking sound sort of like a diesel engine for about 1 second. Any update on this situation? Is this a problem and it is NOT normal? Thanks.