Well...my dad used his diagnostic scanner on the camaro today in search of the reason why me car is running rich. I couldn't find that, but we did notice another thing. The knock retard at idle is about 1..and then when you stab the throttle...or go WOT the car picks up 10 degrees of knock retard. Is this normal, and if not what would the cause be?

Kyle

 

You shouldn't see any knock retard at idle, and only occasional knock at WOT (often at shift points).

If you have these levels of retard constantly, you need to determine if its retard in response to "real" knock, or in response to "false" knock. Put some 100-octane unleaded racing fuel in it, and see if the knock goes away. That would verify real knock, if the retard disappears. If it doesn't disappear, there's a good chance its "false" knock. You would need to identify the source of mechanical noise that is fooling the knock sensor. What kind of rockers do you have with that cam?

 

I have Comp SA pro-mags...what could be causing false knock?

 

ummmmmm.... the Comp SA pro-mags. The are full roller rockers, and very noisy. GM put full roller rockers in the LT4 engine, and came up with a new "knock module" that filters out the noise signature from the roller rockers, and prevents false retard. I thought just about every 1994 and newer LT1 owner on the planet already had one of these... aka the "LT4 Knock Module".

Do you have one already?

You also have poly motor mounts listed. The knock sensor is located right next to the motor mount? Is there any chance there is some metal-to-metal contact in the mounts, or that you left a bolt or two loose when you installed them?

 

Yeah, I know these rockers are noisy, but wasn't sure if that would be picked up by the KM. Yes, you guessed..already have the LT4 knock module. I will go throw the car on some ramps and check it out.

EDIT...I just checked the mounts....all bolts are tight. The only other thing I see is...the one header primary..barely touches the motor mount. Could this be the problem? Its not dimpled or anything..its just like kinda lying on it slightly. On a side not...could this be why my car is noy performing like I believe it should at the track?

 

Anybody?

 

exhaust leak will make the car think its lean and add fuel to compensate to the point of pre detonation causing knock retard ...it happened to me..and yes this is why your car isnt runnign like it should

 

I don't have any exhaust leaks, so that is out...any other suggestions? I a, looking around and can't find why I am picking up knock. I will try some high octane race fuel..and see if its real knock. Whats next?

 

Your LT's are enough to cause false knock muchless your RR's.
An LT-4 KM won't help and is a waste of money. Do a board search and get the correct resistor to put inline with your knock sending unit.Or have it tuned out.
Do this AFTER ya have ruled out real knock.Like Injuneer said get some 100 octane unleaded and see.
The running rich could be from an injector up grade,fuel pressure,exhaust leak,retarted timing,several differant sensors not reading correct,restricted air intake,mass air meter, need further tuning,to name a few.

 

OK, i found 2 things that I am sure would cause false knock. One motor mount bolt was pretty loose, fixed that..and the header primary was lightly touching the motor mount. I dimpled that and now have just over a 1/4" of clearance.I sent my scan results to Injuneer and madwolf. I read Injuneers page about datamaster readings, and all values look good except for the Knock retard, but i am not really experienced. I just drove it and when I first took off out off the driveway...it showed some knock. After it about a mile it was gone, I filled up with gas....took off, and drove around for a while...No more knock was shown. This is weird I tell ya. I think it may have been a combination of bad gas, and the loose motor mount bolt, and the LT primary that was rubbing. Tomorrow I am going to put some race gas in it, and drive around and see what happens. Does this sound like a feasable explanation for my issues.

 

Take it out and BEAT on it and see,thats the only way to tell.Driving like Mom is in the car don't tell ya nothing.

 

Thats how I always drive man. Actually I drive faster with mom in the car....thats the only way she'll shut her trap...she closes her eyes and holds onto the door panel for dear life. lol

 

 

Yogi once reminded me, to have respect for your mama. Remember, initially, you were a great pain to/for her.
OK, the resister technique noted above is fine. Afterall, how did we survive prior to knock sensor technology? Providing you consider the present knock detection, technology. Anyway, with the KS circuit disabled, how does one determine real knock. 100 octane is fine for tuning purposes, if available. However, there is no guarantee 100 octane would be adequate in some instances. On it's own merits, may not positively determine false/real knock. IOW, it could STILL be real. I say forget about the 100 octane and rig up a knock sensing ciruit using head phones. This type of knock identification is actually more prominent/precise in identifying knock that the present OEM method, AFAIC. Something to consider.

 

While I agree that an exhaust leak will cause a "false lean", and cause the PCM to add fuel the engine doesn't need, I can't think of any possible reason this would lead "to the point of pre detonation causing knock retard". Its running lean that causes knock. Pouring in excess fuel will reduce combustion chamber temps and eliminate knock.