MR01Z28

I am not to sure if this is the place i want to post this but here goes. lol
I have an 01 Z28 auto I took it to the track and it was spark knocking real bad in the higher rpm's. So I changed the plugs and put in the acdelco irridums and it got to full running temp after i got them in and took it out for a few wot pulls and burn outs and never heard it spark knock, so today me in my wife were out with the t-tops out and she wanted me to hit it and once it got around 5k it started spark knocking again. So I have been reading and I wanted to ask on here I am looking to put a 160 t-stat in it and see if that gets rid of it. The slp t-stat in the summit magg. says it can reduce spark knock so i was wondering if anyone else has has this problem. I only got a mac catback and slp lib and k&n, so I didnt think I had to get it tuned just cause of that until i get some lt off road y and gears. So I was wondering if I could get any input on the 160 stat? thanks

SweetS10V8

iTrader: (4)

Forget the t-stat, its not the way to fix knock. Fix your tune or get higher octane fuel.

MR01Z28

I always run 93 no matter what fuel I have ran I have ran each type a few tanks in between different brands of 93. I guess i got to get my lt and ory so i can get it tuned all at once. Which is bs with it being basically stock but whatever thanks

SSTYCOON

iTrader: (2)

are u sure its spark knock? u know what it sounds like? it mite be just in your head. Its probably something else.

MR01Z28

Yes I know it is spark knock this may be my first LS1 but not my first car I had this happen in my 5.0's when I had the timing to far advanced or was just running the wrong octane. I was not the only one that heard it again today my cousin that is a mechanic/ state inspector that has a LS1 also heard it today so I know it is not in my head thank you.
So my next step is to do the t-stat because my car runs at around 210. And if you know anything about engines the hotter they run and when they are over heating they tend to get the spark knock sound so I want to lower the temp of the engine to see if that helps it go away.

LS1-450

iTrader: (33)

^^^^

Hey, people are just asking & making statements to try to help you. So, no need to get smug.

The knock can be caused by a number of things. Could be coolant temp, but a 160 stat won't reduce it in traffic if the fans aren't set to come on @ a lower temperature. So, fan temp settings need to be added to the list while tuning.

It's very likely that your MAF sensor is dirty so that it isn't reading the correct velocity of air entering the intake. So, the PCM doesn't send enough fuel for the amount of air entering & you get spark knock during high air movement (5K + RPM). Get some die electric cleaner or rubbing alcohol & a Q-tip. Very carefully clean the 3 resistor wires on the MAF. Also, run a bottle of Techron injector cleaner in the tank or have your cousin mechanic clean the injectors @ the rail w/ Echlin Pro clean or another proffessional grade injector cleaner.

If this doesn't do it, check your plug wires.

These things should be done before anything else.

MR01Z28

Thanks for the last reply. I was just alil offended about being in my head. But i am not understanding why it would need to be tuned if all I have is a catback with a slp lid and k&n filter. Will try the cleaning of the mass air. thanks

02fbody35th

I was having the same problem bro, turns out the previous owner had a hand held tune in the computer that was killing the timing so i had the dealer return it to stock and the problem was gone. if you dont have a crappy hand held tune it might be bad gas. if I use any gas except 93 octane from shell i always get a bad high rpm ping. If not that you should deffinatly use a maf cleaner and clean the maf. A 160 t stat might help but thats not your problem it should run fine with a stock t stat so i would try tracking down the real problem before covering it up. http://www.toptiergas.com/retailers.html check out one of these gas stations in your area. you might not believe it but poor quality gas makes a HUGE differnce. I gave you everything i know man It took me a while to figure out my prob. so i hope this helps.

Mart00SS

iTrader: (19)

/\
x2 on this.
I've seen plenty of stock ls1s with spark knock due to a lean condition caused by a dirty MAF. Easiest way to do it is to take it apart. Mine appeared clean from the back but a view from the front showed a hearty buildup of gunk.

SweetS10V8

iTrader: (4)

Stock LS1s also have valvetrain control issues that can be mistaken for spark knock. Right around 5000 sounds right too.

MR01Z28

Thanks I will be cleaning it when I get home from work tomorrow. I am going to use the rubbing alcohol. Unless someone can let me know where I can buy the die electric cleaner. I have only heard about it never used it. Thanks alot I hope this helps I am going to try to stick with either texaco or shell we have both within 2 miles of my house. thanks again

cpw006

I had the same issue, around 4500 to 5000 it would do it. I took the advice of LS1-450 and cleaned the 3 little MAF sensors very easily with alcohol and a Q-tip along with a new air filter(needed one anyway) and that solved my problem. They were not extremely nasty, but you could tell the difference in them after I cleaned them.
Thanks

bwkmaro

it could be valve noise at 5k the lifters can start not keeping up but crc makes the cleaner you can get it at any autoparts store. its a hit or miss though cleaning a maf.

sabersaw30

iTrader: (10)

You need to get you a scan tool and see how much spark knock you are getting.something that reads live data.I use a little cheap auto X-ray.Here is a nice scan toolhttp://marylandspeed.com/aeroforce-i...x01-p-404.html

Blk98Vert

iTrader: (2)

What were the plugs gapped at, they should be at .04