Knocking problem
Thread Starter
Heel & Toe
Joined: Aug 2008
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Using Shell V-Power Premium, in Finland Shell advertise that it is +99 octane. Other gas stations sells 95(oct)E10 and 98(oct)E5 .Shell is the only station which sells 95(oct)E10 and V-Power.
Thread Starter
Heel & Toe
Joined: Aug 2008
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Had this exact same problem. I'm positive it's valve train noise. I would get 2-3* timing pulled no matter what I did, had the timing down to 8* and would still pull timing. I am running Yella Terra's w/ Comp Cam R lifters.
Finally I put a tank of Sunoco 100 and left the timing @ 8* and it STILL pulled timing. So I knew it was false knock. I just detuned them alittle, I agree w/ not turning them off all together. There is a table in HPT that allows you to change the senstivity once you go over a certain RPM.
Finally I put a tank of Sunoco 100 and left the timing @ 8* and it STILL pulled timing. So I knew it was false knock. I just detuned them alittle, I agree w/ not turning them off all together. There is a table in HPT that allows you to change the senstivity once you go over a certain RPM.
Melting Slicks
Joined: Jul 2008
Posts: 3,002
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From: Houston Texas
2018 Corvette of Year Finalist
2017 C5 of Year Finalist
Take a look at your datalogs. If you are only using 50% throttle, you will be in a different cell in the timing table than you are at WOT. The timing values at lesser throttle percentages are usually higher. You will need to lower timing in the part throttle range.
Tech Contributor
Joined: Apr 2007
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From: Forney Texas
Racer
Joined: Jul 2010
Posts: 252
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From: Kingwood TX
Mine was doing the same thing... Turned out to be false knock the 98 computer was expecting from the sudden volume of air / fuel being added... Basically I increased the number in the Burst Knock Retard Delta Cyl Air to 6 and she straightened right out!
Le Mans Master
Joined: Oct 2005
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From: Metro Detroit Michigan
As others have mentioned, putting in a much higher octane than needed can still be a useful diagnostic tool. If knock doesn't change, it's probably not really knock.
Tech Contributor
Joined: Apr 2007
Posts: 10,924
Likes: 78
From: Forney Texas
Ok, just for grins, go in the spark retard tab> Enable delta cylinder air and max everything above 2800 out by setting the value to 8. Then go to the vs. RPM tab and put 0 in everything from 2800RPM up. Tell us what happens. I've never seen burst knock show up as KR unless it was real burst knock, hence the need for another independent PID. It should be raised if it's stock values anyways. 
Thread Starter
Heel & Toe
Joined: Aug 2008
Posts: 20
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My buddy has the datalogs on his computer, HPT is his so i can only tune the car on weekends. But i am going to buy HPT for myself, so all this is going to be much more easyer to try out.
I will try ZAVOD and BLOWNBLUEZ06 advises as soon as i get HPT for my buddy of from the store.
I will try ZAVOD and BLOWNBLUEZ06 advises as soon as i get HPT for my buddy of from the store.
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Thread Starter
Heel & Toe
Joined: Aug 2008
Posts: 20
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We was tunin the part throttle tables, the car wont let me even go over 50% throttle without knocking on HPT.
Thread Starter
Heel & Toe
Joined: Aug 2008
Posts: 20
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Ok, just for grins, go in the spark retard tab> Enable delta cylinder air and max everything above 2800 out by setting the value to 8. Then go to the vs. RPM tab and put 0 in everything from 2800RPM up. Tell us what happens. I've never seen burst knock show up as KR unless it was real burst knock, hence the need for another independent PID. It should be raised if it's stock values anyways.
Tech Contributor
Joined: Apr 2007
Posts: 10,924
Likes: 78
From: Forney Texas
Just for the record, you could also have carbon buildup in your cylinders and a seafoam treatment might help with that. I've seen crazy things like clogged catalytic converters cause knock too.
Thread Starter
Heel & Toe
Joined: Aug 2008
Posts: 20
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Ok, just for grins, go in the spark retard tab> Enable delta cylinder air and max everything above 2800 out by setting the value to 8. Then go to the vs. RPM tab and put 0 in everything from 2800RPM up. Tell us what happens. I've never seen burst knock show up as KR unless it was real burst knock, hence the need for another independent PID. It should be raised if it's stock values anyways.
Tech Contributor
Joined: Apr 2007
Posts: 10,924
Likes: 78
From: Forney Texas
If that's the case, pull your codes from the DIC and list them. In case you don't know about that, you have 6 buttons on the right side of your dash that allow you to view different things. 1 is the top and 6 is the bottom. Turn the key on and hit "reset" until all messages are cleared and then hold down button #4 with your thumb. While holding it down, quickly press button #1- 4 times. It will begin listing your codes. You can manually navigate through those codes by hitting #4 again.
List those codes. Probably P1514 or P0106 and then 1278.
Thread Starter
Heel & Toe
Joined: Aug 2008
Posts: 20
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By "stops working" you mean "reduced engine power"?
If that's the case, pull your codes from the DIC and list them. In case you don't know about that, you have 6 buttons on the right side of your dash that allow you to view different things. 1 is the top and 6 is the bottom. Turn the key on and hit "reset" until all messages are cleared and then hold down button #4 with your thumb. While holding it down, quickly press button #1- 4 times. It will begin listing your codes. You can manually navigate through those codes by hitting #4 again.
List those codes. Probably P1514 or P0106 and then 1278.
If that's the case, pull your codes from the DIC and list them. In case you don't know about that, you have 6 buttons on the right side of your dash that allow you to view different things. 1 is the top and 6 is the bottom. Turn the key on and hit "reset" until all messages are cleared and then hold down button #4 with your thumb. While holding it down, quickly press button #1- 4 times. It will begin listing your codes. You can manually navigate through those codes by hitting #4 again.
List those codes. Probably P1514 or P0106 and then 1278.
Team Owner
Joined: Jan 2007
Posts: 29,063
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From: cookeville tennessee
I seen and read in here sometime back that the 185 rockers did make this happen on a few cars. The guys pulled them and went back and the problem did stop... I would try that would be a pretty easy fix if that is the problem if it dont you know it is something more. I would listen to BLOWNBLUEZO6 he has dont alot of work on these cars..... Robert
Le Mans Master
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