Might be best to get a new harness for the sensors just in case your's have corrosion, which is very common.
Might be best to get a new harness for the sensors just in case your's have corrosion, which is very common.
See my truck data in the "My Garage" section here... http://www.ls1truck.com/forums/my-ga...tml#post191709
The problem could be the sensors or corrosion.
It's a known issue that moisture enters the ks hole and corrodes the sensor.
It could also be or more likely the 99 PCM and calibration.
99's typically handle 19-23degs of timing at wot before knock appears.
I would skip on the 99 PCM and upgrade to a 2002 PCM and cal.
Problem solved.
We see this quite a bit from the 99 LCMs.
Nelson Performance
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'94 Chevy Truck: 8.9 et, 408 twins
before you go changing sensors and etc
check the following, loose converter bolts, loose motor mounts, headers hitting frame, exhaust rubbing frame, heat shields vibrating, excess wobbling of crank pulley.
all of these will cause a KR issue
now does the KR spike and dissappear or does it carry out thru entire run? a spike is false, a carry out is real KR
or do it old school and listen for pinging then back off 2-3 * [this was the method used before knock sensors] in some cases add timing till it quits making power then back it off 2-3*
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it ain't that I'm too big to listen to the rumors, It's just that I'm too damn big to pay attention to 'em..That's the difference
Quick, when on I will see KR almost any and all rpm and any throttle % over Maybe 20%. It does this with 93 octane and 2 bottles of booster on flat ground and in 20* weather. We tried locking the timing in at 10* and still saw KR as soon as I started taking off. I know converter boots are tight, haven't been installed over a month. Headers touch nothing, no heat sheilding left on exhaust. I though my tip might have been touching my hitch so I insulated it with rubber. No difference. I've never heard this truck make any pinging. I know what it sounds like for sure. But the exhaust is so loud I don't know if I would hear it if it did.
99 silverado 2500 4x4 ec lb, lq4 with 243 heads, pace setter long tubes, true duals with x pipe and bullet mufflers, comp 222 224 112 cam, 8.1 truck injectors, 4l80e with 2800 stall, 373 gears, 285 75 16 tires, efi live tune in progress, 350rwhp 360tq, 11.8 average mpg mixed driving
Nelson, if I switch to an 02 os I don't need the actual pcm right? I can just download the 2002 os from Holden crazy and flash it on my pcm? I tried that when I first started Trying to tune this thing. Still saw the KR plus I had a battery light stuck on. Switched back to the 99 os and no more batt light. All the work done on this tune is on the 99 os. Like ve tuning using the ltft and stuff. It was alot of time and we got the afr and fuel trims looking pretty good now. Just getting our ass kicked by the timing cause of KR. If I go 02 os I loose all our progress correct?
99 silverado 2500 4x4 ec lb, lq4 with 243 heads, pace setter long tubes, true duals with x pipe and bullet mufflers, comp 222 224 112 cam, 8.1 truck injectors, 4l80e with 2800 stall, 373 gears, 285 75 16 tires, efi live tune in progress, 350rwhp 360tq, 11.8 average mpg mixed driving
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