Rattle at high rmp...is it detonation? is my motor pooched?

From Vortex Buicks:
cc = Cross Counts

Cross Counts are the number of times that the factory O2 sensor has crossed from lean to rich across the stochiometric point (0.441v) during the sample rate of the scan tool. The more active the sensor is, the better job the ECM will do in keeping the A/F at the desired stochiometric ratio for idle and part throttle driving. At wide open throttle, it is not used. Many scan tools may show this number as a cumulative addition so that the first frame may be 10 and the second may be 30 which means the second frame was actually 20. When the total reaches 255, it resets to zero and starts over.
Given that a tool like the ScanMaster samples at approximately 1.4 second intervals and more sophisticated tools like PowerLogger may provide 20+ fps, one must take this into consideration when looking at the results.
Something like 10-40 cross counts per 1.5 seconds is probably normal. An O2 sensor that is sluggish and consistently is on the low end (count-wise) should be replaced. O2 sensors are cheap and it does not cost much to replace one periodically anyway. If you don't, gas mileage and drivability will soon go down hill.
As stated prior, leaded racing fuel will often drastically shorten the life of the O2 sensor. Symptoms are reduced output, sluggish cross counts, and/or a check engine light. Many believe the Denso sensors resist degradation much longer than do the factory AC sensors. When leaded gas has been used, even the Densos will show a sluggish cross count, but, will sometimes clean back up with use. Watch the counts, if they don't recover to a normal level, put another one in if you want optimum mileage and part throttle performance.
If you have a chip that provides an Open Loop idle, it will probably show zero cross counts at idle and this is normal. Check the cross counts at cruise. Also, do not expect cross counts at wide open throttle.
i've got a new denso. it might be pooched. i have a spare i will throw in.
 
Like to ask. who did you buy the car off of.
I live in Ontario Canada, his first name is Blake, would rather not give his full name out over the open forum. I have spoken to him a few times since i have purchased it. sounds like he dint know much about the car.
 
Top