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I have shagged knock sensors, they cause a split second of knocking on startup then read zero on idle, recently had the car tuned and they were causing timing issues, and fighting the SAFC and major loss of power....

Has anyone replaced their knock sensors?

Where are they located?

What the hell do they look like......

Edited by 4core

If you are getting timing issues during tuning, then maybe the sensors are doing their job, and you have genuine knock issues.

Have you run an ECU diagnostic to determine if there is a problem with the sensors?

they cause a split second of knocking on startup then read zero on idle
Ever thought it might be the "noise" of the starter motor?

They are located in the block, under #2 and #5 inlet runners.

If it was the starter motor it would be a consistent knock yes? no? Mine will knock anywhere between 9, up to the highest ive seen 135. If it was the starter it would do it all the time right?, once warm the knocking on startup is gone....

the guy tuning my car said he can feel the knock (big lean out at 6500rpm but fuel pressure is perfect) but the SAFC 2 is not picking it up correctly. when i told him about the split second knocking on start up, he said rooted sensors.

You said it does it on startup, but not on idle. The starter only works on startup, and isn't working once the engine is idling.

If the fuel pressure is fine, but you are getting a leanout at 6500, then it's the tune, not a knock sensor.

AFAIK, rooted sensors do nothing (ie have no effect on anything), rather than interfere with workings.

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