what is knock?

[V6-Sauce]

hey fellas I'm new, I just a nice gn last summer(stock), it's in storage now. Can somebody explain what Knock is and the location, does it make a noise coming from the knock sensor if it's bad.....can certain upgrades create more knock...what do i need to know so i don't get in trouble with this, Since i just got the car should i replace it.....i got no scan tools, do u need one to see if it's got knock?

 

[Audie1]

You need to do lots of reading, especially if you are planning on making your car faster. Some good links below, the more that you know the better off you will be. If your car is all stock and you have not adjusted anything you don't have to worry about knock too much. Keep it tuned up good and run high octane in it. Your knock sensor retards timing when it senses knock/ping in your engine. Check out the links below. Welcome to the Dark Side

Vortex Turbo Buick Performance

Turbo Regal Web Site

 

[bmackinnon]

Your knock sensor retards timing when it senses knock/ping in your engine.

When we refer to knock (detonation/ping, usually from a lean air/fuel mixture, too much timing advance, and/or inadequate fuel octane), we are talking about HOW MUCH the sensor is retarding the timing..... otherwise known 'Knock Retard' and abbreviated KR.... while the ecm DOES retard the timing, knock WILL (still) result in blown headgaskets, or worse..... thus the reason these cars MUST be tuned for NO KNOCK....

If you don't already have one, spend the VERY FIRST dollar on your car on a scantool of some sort (Scanmaster is used by many) which will read KR, oxygen sensor volts (O2's) and every other sensor/data point the ecm uses, so that you can accurately assess/troubleshoot the car's state of tune.... and DO NOT run the car hard (wot) until you have verified a proper tune...

Excellent links above.....READ, READ, and READ.... Welcome!

 

["Turbo-T"]

hey fellas I'm new, I just a nice gn last summer(stock), it's in storage now. Can somebody explain what Knock is and the location, does it make a noise coming from the knock sensor if it's bad.....can certain upgrades create more knock...what do i need to know so i don't get in trouble with this, Since i just got the car should i replace it.....i got no scan tools, do u need one to see if it's got knock?

Knock is a sound caused by abnormal detonation outside the flame front within the combustion chamber. Yes certain upgrades can create knock...like adding more boost without enough fuel/alcohol....or advancing the timing too much. No it doesn't make a noise from the knock sensor, the knock itself comes from inside the combustion chamber. It's a metallic pinging sound when audible to the human ear. All the knock sensor does is detect it and then send a signal to the ECM to back off the timing enough to curb it.

Knock is like death and taxes...inevitable....and can mean death to any engine, especially a forced induction engine like a turbo car or a supercharged car....but you can help keep it at bay using a Scantool and knowing what to look for.

My advice is spend $280 and get a Scanmaster. Hook it up to your car's ALDL port. Place it on top of the gauge cluster. And keep the boost down to 10-12 and anytime you go to get on it, keep an eye out for where it says "knock retard". If it starts registering anything over 2.0 degrees, immediatley get out of the boost until you've determined why.

Also keep good 92-93 octane fuel in your tank; don't even plan on running 87. Not worth it. Make sure your in tank fuel pump is a newer high flow one, not the old stocker. Make sure the pump is on a hot wire kit. Keep the chip timing down. If you afford $530 get an alky injection kit. The alky helps quench knock so you can safely run higher boost pressures.

Follow these simple rules and don't ever ever allow any KR to happen and you won't have to come here asking "how do I change my blown head gaskets?"....or worse "why did my engine suddenly explode?"

 

[turbojd]

As was said above, a scanmaster is a must to have to read knock!! Also do plenty of reading on these cars to help avoid some future problems that can be avoided.

 

[TurboBuRick]

(Knock or pre-detonation) When fuel ignites prior to spark. It hits the pistons like a sledge hammer. The fuel actually ignites while the piston is traveling upward. Not good. It will usually take out the head gaskets real quick. Those are the weak link.

Turning up boost without adding more fuel will get you knock. So do your homework.

Rick

 

[1000MileStylez]

knock is your worst enemy, build a race motor and nightmares will follow. followed by cold sweats and shortly followed by high fever. There is no cure for this

 

[Jerryl]

Good advice here.

Knock is like an ex-wife with kids.
You knock her up, now she keeps knocking on your door looking for a handout, inreturn for a boost favor. Can be a hard habit to get rid off.

 

[V6-Sauce]

thx everybody, going to ken's national performance in t.o this spring for a couple of things, like exhaust, injectors(36 bluetops hopefully), chip, boost gauge, fuel pump, air cleaning kit, it's already got the hotwire kit and regulator, nothing too extreme...I want to keep her safe, he's a good guy, he know what to do

thx again guys...

 

[TurboBuRick]

Good advice here.

Knock is like an ex-wife with kids.
You knock her up, now she keeps knocking on your door looking for a handout, inreturn for a boost favor. Can be a hard habit to get rid off.

LMAO! Good one Jerryl!

 

[1000MileStylez]

thx everybody, going to ken's national performance in t.o this spring for a couple of things, like exhaust, injectors(36 bluetops hopefully), chip, boost gauge, fuel pump, air cleaning kit, it's already got the hotwire kit and regulator, nothing too extreme...I want to keep her safe, he's a good guy, he know what to do

thx again guys...

learn as much as you can on your own. When yoru testing and tuning by yourself you will want to know what to do when something happens when you are stuck somewhere