Knock Problem
12-27-2003, 02:37 PM
#1
Launching!
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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?
12-27-2003, 03:45 PM
#2
I think the only way to know for sure is to put some unleaded racing gas in there and do some more logging. If you are still seeing knock then it's safe to assume it is indeed false.
12-27-2003, 09:17 PM
#3
Launching!
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Yeah, I have a little (not much to matter) VP 103 in there- but I'll try a full tank. This has been a 3 day problem solving thing for me- posting on here was a last resort...sigh