Dash Knocking
Thread Starter
Racer
Joined: Mar 2011
Posts: 337
Likes: 1
From: Mechanicsville Md
Dash Knocking
OK get in the car 27 degrees outside. I start driving my car and I start hearing a knocking sound coming from behind the dash. Thought is was the key fob but I held it and the knocking continued. Very sparatic and not related to bumps or agressive movement back and forth. Sitting at idle nothing, accelerating and I hear it and when the car warms up no knocking or very far and few in between. Has anyone experienced this. Definitely not and engine noise. I'm thinking it the HVAC actuators but I move the heat up and down and switch between vent, heat and defrost and no noise. Just happens every so often.
Drifting
Joined: Jul 2003
Posts: 1,647
Likes: 2
From: Peoples Republik of Kalifornia Ka
I seem to have the same thing going on. Sounds like something is rattling around in the dash. I only notice it driving in town under 40 MPH. Dont hear it on the freeway. It drives me nuts but I guess not enough to tear my dash down and look. If you figure it out let me know. I wonder if it could be something in the engine bay or under the car? I'll keep looking I guess...
Le Mans Master
Joined: Mar 2011
Posts: 6,835
Likes: 302
From: Columbia SC
In that weather it was probably your knees knocking before the car warmed up.
OK, seriously: Post 1 indicates it may be temp related (or just started for some reason). Post 2 and 3 don't say if it happens all the time or not or if it is temp related. That info would be helpful.
OK, seriously: Post 1 indicates it may be temp related (or just started for some reason). Post 2 and 3 don't say if it happens all the time or not or if it is temp related. That info would be helpful.
Intermediate
Joined: Sep 2001
Posts: 26
Likes: 0
From: Albquqerque NM
I had a noise (not rpm related) coming from between the engine and the tunnel. It was a 6 inch heat shield coming off the starter solenoid, I could re-create the sound my pushing on the shield from the bottom of the car with a pry bar (hard to get to since the exhaus is in the way). I was able to pry the shield toward the tunnel, away from the starter and the noise was reduced about 90%. Someday I need to remove the exhaust and zip tie or tweek the shield a bit more. The sound wouldn't happen until the car warmed up a bit, I think because the engine would heat and either the metal on the shield would expand or the engine mounts would loosen up a bit, it was also worse (louder), when makeing left hand turns since the starter.tunnel distance would be closer as the engine moved a bit.
Jon Albuquerque 1997 coupe
Jon Albuquerque 1997 coupe
Drifting
Joined: Feb 2004
Posts: 1,250
Likes: 0
From: Katy TX
St. Jude Donor '08-'09
i had the SAME thing. it sounded like something knocking around behind the dash, more of a "thunking" sound. Well believe it or not..
the sound was travelling from my roof and echoing off the dash making it sound like it was in the tunnel behind the dash.
i released my two front latches, left the rear attached and drove about two blocks at 20-30mph and latched it down again as i was moving and no more noise. Craziest thing, but thats what it was. And mine started doing this after we had a cold snap here.
the sound was travelling from my roof and echoing off the dash making it sound like it was in the tunnel behind the dash.
i released my two front latches, left the rear attached and drove about two blocks at 20-30mph and latched it down again as i was moving and no more noise. Craziest thing, but thats what it was. And mine started doing this after we had a cold snap here.
Advanced
Joined: Sep 2012
Posts: 81
Likes: 0
i had the SAME thing. it sounded like something knocking around behind the dash, more of a "thunking" sound. Well believe it or not..
the sound was travelling from my roof and echoing off the dash making it sound like it was in the tunnel behind the dash.
i released my two front latches, left the rear attached and drove about two blocks at 20-30mph and latched it down again as i was moving and no more noise. Craziest thing, but thats what it was. And mine started doing this after we had a cold snap here.
the sound was travelling from my roof and echoing off the dash making it sound like it was in the tunnel behind the dash.
i released my two front latches, left the rear attached and drove about two blocks at 20-30mph and latched it down again as i was moving and no more noise. Craziest thing, but thats what it was. And mine started doing this after we had a cold snap here.
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Drifting
Joined: Feb 2004
Posts: 1,250
Likes: 0
From: Katy TX
St. Jude Donor '08-'09
Thread Starter
Racer
Joined: Mar 2011
Posts: 337
Likes: 1
From: Mechanicsville Md
I replaced my OPS without removing the intake. I disconnedted the vacuum line between valve covers and pryed the lines around to gain access to the OPS. I'm going to look to see if I F%ked something up where I have induced a vacuum leak. Knocking started/noticed after that. I'll check this weekend.