Mazda Rotary Club

Cars by Model Type => 3rd generation RX-7's => Topic started by: davyv on November 30, 2007, 08:07:08 PM

Title: Knock
Post by: davyv on November 30, 2007, 08:07:08 PM
Hi all, on a warm engine, if i rev my car at 4k rpm my knock reading goes up to about 120, is that ok, or bad. Its quite often about 80-90 when driving,Thanks.
Title: Knock
Post by: ro284 on November 30, 2007, 08:32:01 PM
My knock level is around 65 and heat light flashes at a quick blip to around 2800 revs, just a quick flash, i\'m not driving the car much at the moment till i get the car mapped after fitting large bore DP to go with arge bore de-cat, i thought it may be a faulty knock sensor, so i changed that for a known good one, exactly same reading! so the original was ok!
Bob
Title: Knock
Post by: gsb876 on November 30, 2007, 08:49:20 PM
Remember if the car backfires the knock reading will go through the roof
Title: Knock
Post by: Ricco_04 on November 30, 2007, 10:53:18 PM
Quote from: davyvHi all, on a warm engine, if i rev my car at 4k rpm my knock reading goes up to about 120, is that ok, or bad. Its quite often about 80-90 when driving,Thanks.

120 knock would probably have damaged the engine (so im told) so this would probably point to the sensor picking up some noise of the same frequency? Is this 120 reading when stationary and you bring the rev\'s up to 4k?

80-90 is too high a value when driving imo.
Title: Knock
Post by: davyv on December 01, 2007, 12:51:19 AM
Yes 4k rev when ststionary, with a warm engine.The engine has only done about 1300 miles and has been  run in and mapped. Could the mapping be out.
Title: Knock
Post by: banned advertiser on December 01, 2007, 01:06:12 AM
Make sure the old heat sensor is secure, been told this flapping around will cause light to go off.