Engine Knock

BoostedCivic · 05-29-2008

Damn, this aint good... I have a engine knock and most likely will have to wind up takin this thing into a shop somewhere.. Anyone know what could be causing it?

Urbanmyth · 05-29-2008

This information is mainly DSM specific, however these concepts can be applied to most any car. What I have done here is created a list of ways to get knock, and how to get rid of it. Most this information has been pulled from DSM Tuners. Enjoy!

Detonation (also called "spark knock") is an erratic form of combustion that can cause head gasket failure as well as other engine damage. Detonation occurs when excessive heat and pressure in the combustion chamber cause the air/fuel mixture to auto ignite. This produces multiple flame fronts within the combustion chamber instead of a single flame kernel. When these multiple flames collide, they do so with explosive force that produces a sudden rise in cylinder pressure accompanied by a sharp metallic pinging or knocking noise. The hammer-like shock waves created by detonation subject the head gasket, piston, rings, spark plug and rod bearings to severe overloading.

Mild or occasional detonation can occur in almost any engine and usually causes no harm. But prolonged or heavy detonation can be very damaging. So if you hear knocking or pinging when accelerating or lugging your engine, you probably have a detonation problem. Things that can cause knock:

1. Having too low of octane fuel
2. Carbon build up in combustion chamber
3. Timing being advanced too much
4. Too hot of intake temperatures
5. High engine temperatures
6. Lean fuel mixture

Knocks are the fastest way to melt down an engine so here is things you do to stop it or prevent it:

1. Get a bigger intercooler
2. Install a colder spark plug
3. Use higher octane fuel
4. Retard your timing
5. Block off your EGR (EGR overtime causes carbon buildup)
6. Use a coolant additive such as water wetter
7. Check and fix any boost leaks
8. Turn your boost down
9. Use an oil catch can on your PCV system
10. Add more fuel

peddler · 05-30-2008

Urban thanks for posting such a great reply. That is good information to know.

BoostedCivic · 05-31-2008

Wow Urban, Thanks alot bro. Gonna give this a shot later today and see if it doesn't help.

KyleAdkins · 05-31-2008

Nice Post.

EagleAutosports · 06-07-2008

Great info.

05-29-2008	#1 (permalink)
BoostedCivic Member Join Date: May 2008 Posts: 42	Engine Knock Damn, this aint good... I have a engine knock and most likely will have to wind up takin this thing into a shop somewhere.. Anyone know what could be causing it?

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05-29-2008	#2 (permalink)
Urbanmyth Moderator Join Date: May 2008 Location: Columbia Posts: 65	This information is mainly DSM specific, however these concepts can be applied to most any car. What I have done here is created a list of ways to get knock, and how to get rid of it. Most this information has been pulled from DSM Tuners. Enjoy! Detonation (also called "spark knock") is an erratic form of combustion that can cause head gasket failure as well as other engine damage. Detonation occurs when excessive heat and pressure in the combustion chamber cause the air/fuel mixture to auto ignite. This produces multiple flame fronts within the combustion chamber instead of a single flame kernel. When these multiple flames collide, they do so with explosive force that produces a sudden rise in cylinder pressure accompanied by a sharp metallic pinging or knocking noise. The hammer-like shock waves created by detonation subject the head gasket, piston, rings, spark plug and rod bearings to severe overloading. Mild or occasional detonation can occur in almost any engine and usually causes no harm. But prolonged or heavy detonation can be very damaging. So if you hear knocking or pinging when accelerating or lugging your engine, you probably have a detonation problem. Things that can cause knock: 1. Having too low of octane fuel 2. Carbon build up in combustion chamber 3. Timing being advanced too much 4. Too hot of intake temperatures 5. High engine temperatures 6. Lean fuel mixture Knocks are the fastest way to melt down an engine so here is things you do to stop it or prevent it: 1. Get a bigger intercooler 2. Install a colder spark plug 3. Use higher octane fuel 4. Retard your timing 5. Block off your EGR (EGR overtime causes carbon buildup) 6. Use a coolant additive such as water wetter 7. Check and fix any boost leaks 8. Turn your boost down 9. Use an oil catch can on your PCV system 10. Add more fuel

05-30-2008	#3 (permalink)
peddler Junior Member Join Date: Oct 2007 Location: Lockston Posts: 16	Urban thanks for posting such a great reply. That is good information to know.

05-31-2008	#4 (permalink)
BoostedCivic Member Join Date: May 2008 Posts: 42	Wow Urban, Thanks alot bro. Gonna give this a shot later today and see if it doesn't help.

05-31-2008	#5 (permalink)
KyleAdkins Member Join Date: May 2008 Location: Oakdale Posts: 39	Nice Post.

06-07-2008	#6 (permalink)
EagleAutosports Site Administrator Join Date: Apr 2008 Location: Mebane, North Carolina, USA Posts: 229	Great info.