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odd boy
March 6th, 2009, 08:48 AM
Hi,

I am trying to remove the knock from Camaro 98. I haven't tuned the AFR or the spark deg and it does a lot of knocks at high RPM. Then I pulled some deg but the power become less and the knock still there, even I tried to put more fuel (11.2) and nothing happened more than power loss.

Please note that the fuel pump was checked and found K.

joecar
March 6th, 2009, 10:34 AM
Check:
- engine coolant temperature;
- carbon deposits;
- spark plug gap;

Try higher octane (100+ unleaded) if available, to see if knock stops.

You said you tried reducing timing and richening the AFR (what does wideband indicate...? Or, what do HO2Sx1 voltages show...?).

Post some log files (include DYNCYLAIR_DMA)... does KR have a sawtooth pattern...?

Also diagnose the knock sensors (see if they produce a signal when they shouldn't)...

Can you audibly hear the knock...? Are you sure nothing is virbrating/banging triggering the knock sensors)...?

Is the KR always 4 degrees, or does it vary...?

Stealth97
March 6th, 2009, 11:15 AM
What is the compression ratio? Stock or heavily modified?

odd boy
March 6th, 2009, 05:30 PM
Check:
- engine coolant temperature; Checked, okay
- carbon deposits; Checked, okay
- spark plug gap; Checked, okay

Try higher octane (100+ unleaded) if available, to see if knock stops. Will do and get back to u

You said you tried reducing timing and richening the AFR (what does wideband indicate...? Or, what do HO2Sx1 voltages show...?). WB reads 11.7 then I put more fuel up to 11.2

Post some log files (include DYNCYLAIR_DMA)... does KR have a sawtooth pattern...? Will do and get back to u

Also diagnose the knock sensors (see if they produce a signal when they shouldn't)... Will do and get back to u

Can you audibly hear the knock...? Yes I do Are you sure nothing is virbrating/banging triggering the knock sensors)...? Checked and found okay

Is the KR always 4 degrees, or does it vary...? Will do and get back to u


Thanks

odd boy
March 6th, 2009, 05:32 PM
What is the compression ratio? Stock or heavily modified? stock compression, and only LS6 mainfold, pulley, cat back and headers.

mr.prick
March 6th, 2009, 06:53 PM
97-98`s are notorious for they`re knock sensors.
You may want to get some new ones.

odd boy
March 6th, 2009, 07:20 PM
but I hear it

mr.prick
March 6th, 2009, 07:25 PM
WOW
Got a log?

odd boy
March 6th, 2009, 07:33 PM
will do tonight

joecar
March 7th, 2009, 01:15 PM
Oh, also check for oil ingestion thru PCV plumbing (look inside intake manifold for oil pooling, and behind throttle blade).

Stealth97
March 7th, 2009, 03:33 PM
How many miles on the Camaro?

I wonder if you can check the misfire data for each individual cylinder (1-8) and see if anything shows up. Could the coils be weak and somehow causing this? Could the cam have been changed without your knowledge and be degreed a bit off? Just thinking out loud.

zrx1200
March 7th, 2009, 05:03 PM
Oh, also check for oil ingestion thru PCV plumbing (look inside intake manifold for oil pooling, and behind throttle blade).
oil will definetly cause it .not overfull?

odd boy
March 7th, 2009, 05:03 PM
will do, he is reparing the trans.

The Alchemist
March 8th, 2009, 08:24 PM
post a log please... timing at 6000rpm should be around 22 to 24 deg depending on octane. knock sensors usually always need a degree of 'tuning" at high rpm. THis can be done by tweaking the sensitivity settings at higher rpm to remove false knock. Post pic of your knock software sensitivity table B i think is the one...on the far right hand side in the 100kpa coluom thers numbers like 1.05, 1.08 or 1.10, 1.15 etc. These can be tweaked by 0.02 to 0.05 to remove false knock....

NASABlue
March 17th, 2009, 04:44 AM
not to hijack,

would solid motor mounts on my 97 vette cause issues?

Thanks.

odd boy
March 17th, 2009, 06:44 AM
I removed the heads, I found that the springs need to be replaced.

Stealth97
March 17th, 2009, 08:19 PM
I removed the heads, I found that the springs need to be replaced.

Any broken springs? How many miles on the springs? Stock or aftermarket?

joecar
March 17th, 2009, 08:38 PM
Were they broken...? Weakened...? If so, then what about the condition of cam/lifters/pushrods and did the valves kiss the pistons...?

odd boy
March 18th, 2009, 10:49 AM
they were Weakened... the valves looked leaking. and the rest found K