Mazda Rotary Club

Cars by Model Type => 3rd generation RX-7's => Topic started by: Sy. on November 03, 2006, 04:53:28 PM

Title: PFC Knock levels
Post by: Sy. on November 03, 2006, 04:53:28 PM
Just wondered what people were gettin on ght epfc for knock levels ?
As im not sure it is the fuel but i get some strange readings some times ....

Can travel along the motorway for 10 min + and have 9/14 and suddenly it goes to 40 sometimes for a nano second and back down . and then be fine for 5 min and do it again ... or 20 min and do it again .

just wondered what other people are getting ?
Title: PFC Knock levels
Post by: nikp on November 03, 2006, 05:01:21 PM
I get very random readings. Can be nice 30 through boost, come of, great readings, then suddenly 71 or something silly.
Title: PFC Knock levels
Post by: Sy. on November 03, 2006, 05:14:33 PM
Yeah .. i get that sometimes .. most i had was 75 . was doing 90 and then 5th to 4th and full boost .. but was only for a split second.
Title: PFC Knock levels
Post by: John Yorke on November 03, 2006, 05:15:21 PM
I have had readings of over 170:eek: for no real reason, came to the conclusion that it must be a 10+ year old sensor gone west, unless you are running unmapped boost levels, cheap petrol [wrong RON] I would not give yourself to many worries, if the above does apply [ie you have altered things since the last mapping session] I would be looking to your next mapping session.
hth
Title: PFC Knock levels
Post by: Sy. on November 03, 2006, 05:47:26 PM
no i not changed anything apart from bigger IC .
170 .. didnt know it went that HIGH lol ... i think itis this v-power fuel . as my mate (in a BMW) has said his car misfire\'s between 3 and 5 min of runing in the morning . He\'s hooked it up to the laptop and everything is working correctly as it should .
Title: PFC Knock levels
Post by: andysmee on November 03, 2006, 06:17:17 PM
I get up to 17/18 when cruising and up to 27 when booting it. Different fuels effect it too, Shell V-power gives high readings, BP Ultimate gives lower reading, Tesco 99 gives high readings.
Title: PFC Knock levels
Post by: gonzoninja on November 03, 2006, 06:40:17 PM
usually I see about 20, think the highest I\'ve ever seen was 28
Title: PFC Knock levels
Post by: stylus350 on November 03, 2006, 06:46:23 PM
I can see 110 starting her up.
Title: PFC Knock levels
Post by: Sy. on November 07, 2006, 03:14:27 PM
Andy . yeah i have found the same . Ultima gives low readings .. and this v-poer seems to give him ones .

110 starting her up .. that could just be your exhaust and the db frequenzy it kicks out .
Title: PFC Knock levels
Post by: nikp on November 07, 2006, 03:17:42 PM
I found v-power gave high readings - so i stopped using it. Maybe i\'ll re-try it again, just to see what difference it makes.
Title: PFC Knock levels
Post by: rmagictastic on November 07, 2006, 03:28:51 PM
i get 4 when booting it, off load i get no more than 15 usually, have on occasion silly readings 60-70 just pootling through town (no boost)

Rmaj
Title: PFC Knock levels
Post by: Herblenny on November 11, 2006, 05:00:57 AM
Knock sensor could give false reading thru other external factors such as transmission.

Most people say reading is somewhat accurate at high load. Also knock level doesn\'t make much difference until high load.
Title: PFC Knock levels
Post by: A7NTY on November 11, 2006, 05:41:40 AM
Its just a little microphone essentially so can pick up loads of things. When you need to worry is when you get high readings and you are accelerating on boost. I like to keep mine below 30.