Knock Problem
Thread Starter
Launching!
Joined: Aug 2003
Posts: 272
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From: Ashburn, VA
Knock Problem I've had a knock problem with my car that just won't go away.
Around 600-800rpm there are many occurances of about .9 to 1.1 degrees knock retard.
Then around 2000-3000 there are some more (1.1-2.3 degrees)
And finally I'll get some random ones further up the RPM band (but much less frequent, on my latest drive had a single spice to 4 and one to 6.6- one at 3450 the other at 4310rpm...the 4310 was under load, the 3450 was slowing down...
The problem is they seem so random- some are at load, some are not...etc.
I've retarded my timing 5 degrees- did nothing. Advanced it 7.5 degrees- and still nothing (I was hoping to trigger more with the 7.5 degree advance).
My LTFT values are all in the -.5 to -2 range, and my air/fuel looks ok.
My exhaust is banging my driveshaft loop- and the car generally rattles like none other since I put a new torque arm on it. Could these rattles & vibrations cause false knock like this? And would the amount of knock retard intensify at higher RPM's- when the banging is louder.
I've tested this theory and I can't pin it to when I hear the DS loop bang, but who knows, maybe it's on a level I can't hear.
Any ideas?
Around 600-800rpm there are many occurances of about .9 to 1.1 degrees knock retard.
Then around 2000-3000 there are some more (1.1-2.3 degrees)
And finally I'll get some random ones further up the RPM band (but much less frequent, on my latest drive had a single spice to 4 and one to 6.6- one at 3450 the other at 4310rpm...the 4310 was under load, the 3450 was slowing down...
The problem is they seem so random- some are at load, some are not...etc.
I've retarded my timing 5 degrees- did nothing. Advanced it 7.5 degrees- and still nothing (I was hoping to trigger more with the 7.5 degree advance).
My LTFT values are all in the -.5 to -2 range, and my air/fuel looks ok.
My exhaust is banging my driveshaft loop- and the car generally rattles like none other since I put a new torque arm on it. Could these rattles & vibrations cause false knock like this? And would the amount of knock retard intensify at higher RPM's- when the banging is louder.
I've tested this theory and I can't pin it to when I hear the DS loop bang, but who knows, maybe it's on a level I can't hear.
Any ideas?
