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Possible Engine Detonation? Please help.

  • Thread starter Thread starter Seraphitia102
  • Start date Start date Mar 5, 2010

Seraphitia102

will post boobie pics for a supercharger
Oct 11, 2004
737
1
16
California
Mar 5, 2010
#1
  • Mar 5, 2010
  • #1
I hear this sound in which I thought it was my exhaust rattling. It sounds like metal vibrating a bit loudly and it's been going on for about more than 3 months.

It just hit me yesterday that what if that sound I hear (in which I think is my exhaust rattling) is actually detonation? I can't seem to single out which direction the sound is coming from. I keep on thinking that the sound is coming from the rear-end side of the car but I can't single out the front either. It feels like I can hear it on all directions.

How long can I drive on a engine that detonates? Is it possible that an engine can be detonating for more than 3 months and still work?

Any suggestions?
 

RedDaemon

10 Year Member
Mar 31, 2005
3,470
9
108
Atlanta, GA
Mar 5, 2010
#2
  • Mar 5, 2010
  • #2
havent seen you on in a long time! i am sorry that youre having problems

what octane gas are you using?
 

wmburns

SN Certified Technician
Aug 14, 2009
5,892
514
204
Houston Texas
Mar 5, 2010
#3
  • Mar 5, 2010
  • #3
When does the sound happen? All the time or just under heavy throttle?

My vote is a bad cat or loose exhaust. I don't think any engine would have lasted for 3 months with chronic detonation happening on a constant basis.
 

Seraphitia102

will post boobie pics for a supercharger
Oct 11, 2004
737
1
16
California
Mar 5, 2010
#4
  • Mar 5, 2010
  • #4
RedDaemon said:
havent seen you on in a long time! i am sorry that youre having problems

what octane gas are you using?
Click to expand...

hello I am using 91 octane gas. I reset my Superchips tune back to 87 octane but I still hear that metal clanging sound... I wonder if my engine can detonate at 87 octane...

wmburns said:
When does the sound happen? All the time or just under heavy throttle?

My vote is a bad cat or loose exhaust. I don't think any engine would have lasted for 3 months with chronic detonation happening on a constant basis.
Click to expand...

It happens mostly when I'm pressing the accelerator under normal driving (defined as 0-40mph not flooring it). I can hear it much louder as I'm passing by another car or a wall (the metal clanging sound bounces off walls and cars)...

I'm hoping my engine is not detonating...
 

trinity_gt

10 Year Member
Jan 31, 2003
3,125
81
99
Canada
Mar 5, 2010
#5
  • Mar 5, 2010
  • #5
My guess, based on your description of when it's happening, is a bad catalytic converter heat-shield. If you've got a manual trans, I'd also check the metal cover near the release arm for looseness.
 
K

Kilgore Trout

Fried or Broiled ?
10 Year Member
Mar 30, 2005
4,749
95
134
Mar 5, 2010
#6
  • Mar 5, 2010
  • #6
Best indicator of detonation is to examine the plugs, if you pull them post up some pics.

Good to hear from you Seriphita I hope you are able to quickly determine what this issue is.
 

Seraphitia102

will post boobie pics for a supercharger
Oct 11, 2004
737
1
16
California
Mar 5, 2010
#7
  • Mar 5, 2010
  • #7
trinity_gt said:
My guess, based on your description of when it's happening, is a bad catalytic converter heat-shield. If you've got a manual trans, I'd also check the metal cover near the release arm for looseness.
Click to expand...

Unfortunately I don't have a manual transmission. I would like to have one. I'm hoping this is just an exhaust-based problem like you mentioned.

Kilgore Trout said:
Best indicator of detonation is to examine the plugs, if you pull them post up some pics.

Good to hear from you Seriphita I hope you are able to quickly determine what this issue is.
Click to expand...

Thanks Kilgore. Will detonation always leave its signature on the plugs? I'll definitely have someone pull out the plugs to see if there's any signs of abnormalities.
 
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