I hooked up an hp tuners to my 99 the other day to scan it. Turns out on wot runs I'm hitting 6 degrees kr. Stock mn6 c5 with vararam and corsa. Also, will adding a dose of higher octane fuel (cam2) help get rid of this knock? Thanks guys!
I hooked up an hp tuners to my 99 the other day to scan it. Turns out on wot runs I'm hitting 6 degrees kr. Stock mn6 c5 with vararam and corsa. Also, will adding a dose of higher octane fuel (cam2) help get rid of this knock? Thanks guys!
Only if it's real knock. If false knock then the higher octane won't change anything.
There is no such thing as good knock. That said, on a stock C5, with a stock tune and running premium gas, you shouldn't have 6* of KR. It may be carbonized, since C5s run pig-rich on the factory tune, and carbon hot-spots may be causing pre-ignition. Try a de-carbonizing treatment.
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There is no such thing as good knock. That said, on a stock C5, with a stock tune and running premium gas, you shouldn't have 6* of KR. It may be carbonized, since C5s run pig-rich on the factory tune, and carbon hot-spots may be causing pre-ignition. Try a de-carbonizing treatment.
Thanks, I'll try that. Another aspect, car has 89k miles. Would it benefit me at all to get some new (read clean) injectors?
he didn't say good knock, he said FLASE knock. Flase knock would be something causing your knock sensors to go off for no good reason giving you 'false knock'. In such a case higher octain wouldn't do squat. Its a pretty common thing and can be cause by something loose hitting or rubbing something else. All you need is a sound or vibration at the right frequency the knock sensors are tuned for and BAM you have false knock.
not saying thats what you problem is, just something to consider before you get too invasive.
he didn't say good knock, he said FLASE knock. Flase knock would be something causing your knock sensors to go off for no good reason giving you 'false knock'. In such a case higher octain wouldn't do squat. Its a pretty common thing and can be cause by something loose hitting or rubbing something else. All you need is a sound or vibration at the right frequency the knock sensors are tuned for and BAM you have false knock.
not saying thats what you problem is, just something to consider before you get too invasive.
Understand that Gonna put half a tank of cam 2 in then scan again, see if its still knocking the same. If it is, I'll start checking for those vibrations/things that could cause false knock. If the knock goes away, then I'll go the other route. Just more curious if old/partially clogged injectors would cause knock. The car has felt like it has been slowly losing HP over the last 20k.
Only 13K (ok......13k race miles) on ours and replacing the valve springs helped 'recover' about 30HP........might check yours if you are seeing a HP loss
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As mentioned it is unlikely you are getting 6* of KR from too much timing--Without knowing all your mods---You quite often get false KR from larger stiffer valve springs from a new cam install--Headers too will create false KR---My opinion is that it is most likely one of two things---When shifting you are getting some KR from the traction control system as system retards timing---OR the 97-99's often suffer from overly sensitive knock sensors--Many people replace them with the newer better sensors from a 2000 or newer car----If you have HP tuers--you an see precisely where the KR is happeneing--see if ot is athe shift points---You can desensitise your 99 sensors with your tuner as well---But be aware then the only way to sense the KR then would be with your ears---or a plug reading-
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how much kr is too much?
Gonna put half a tank of cam 2 in then scan again, see if its still knocking the same. If it is, I'll start checking for those vibrations/things that could cause false knock. If the knock goes away, then I'll go the other route. Just more curious if old/partially clogged injectors would cause knock. The car has felt like it has been slowly losing HP over the last 20k.
