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Does knock sensor fault pull timing and reduce boost?

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Had my spec R since March 2011. Engine and breathing all standard until a week ago.

Since maybe November it has not been making standard boost and has felt quite flat and a bit unresponsive on the throttle.

I have spent a lot of time looking for boost leaks, and last week fitted a new blitz front mount and Gruppe M induction kit, but still only 0.5-0.6 bar and quite flat. It's mostly 0.5 bar but creeps up a little more above 5500rpm under full load.

I tried no bleed solenoid and still makes 0.5 on just the actuator so I think the Actuator is fine. Also have tested the solenoid and it's working fine.

Finally tried a manual boost controller from eBay, I don't think it's a good one was peaking over 1 bar when set to minimum. Put the solenoid back in now so it's now being controlled as standard and only making 0.5-0.6 bar.

Anyway I am getting fault code 34 every journey even if a short trip. I can't find anything online clearly stating what the ecu might change with this fault but this is top of my list now for why my car is flat and under boosting.

Can anyone confirm if it pulls timing with this fault?

Can anyone confirm whether it reduces the solenoid duty cycle so reducing boost?

Anyone recommend where to buy a replacement knock sensor?
 

Cess

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Never had knock sensor troubles with my S15, but many years ago when I had my GT-Four, my knock sensor died.

It did retard timing and cut boost way back, so I imagine the S15 did the same.

Nissan might be your best bet for a knock sensor.
 
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yes if knock is detected it will retard the timing and warn you to get your **** checked out, as in before you spin a bearing.... stop boosting it dude
 
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Hi thanks I only tried the manual controller briefly.
The engine check light has not been on normally, I just see the fault code 34 if I short the two OBD pins so that the check light flashes out any codes.
 
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V power last fill, last few tanks have been premium. Did run it on 95 for a while before though.
 
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I tried the manu controller briefly for diagnosis, to try and isolated whether the solenoid was at fault. I expected minimum setting on the manual controller to be a low boost level. I think it does show it was the solenoid boost control thats making it low on boost. As the solenoid is working it's gotta be the ecu controlling it that's keeping boost low.
 
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She is fixed :)

The knock sensor was knackered. With a multimeter tested resistance as per the service manual and it was open circuit. A friend gave me his from a scrap SR20 and that read about 569 K Ohms as per manual. swapped them over (very hard to reach!) and now my car is proper fast again. :)
 
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Really releived the knock sensor was not reading actual engine knock. It seemed that every time I reset the ECU it would start reducing timing and boost after a couple of hard pulls.

I reckon that of you have a duff sensor the ecu determines this by whether it gets nothing from the sensor when load is high through the rev range. I think it would always be getting something from a working sensor.
 
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She is fixed :)

The knock sensor was knackered. With a multimeter tested resistance as per the service manual and it was open circuit. A friend gave me his from a scrap SR20 and that read about 569 K Ohms as per manual. swapped them over (very hard to reach!) and now my car is proper fast again. :)
right prick of a place, we think the oil filter is hard to get too
 
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yes if knock is detected it will retard the timing and warn you to get your **** checked out, as in before you spin a bearing.... stop boosting it dude
Just to clarify, if knock is detected then it will go in safe mode but will NOT flag a code 34 or light the check engine light. Code 34 only related to a sensor fault, and won't light the check engine light. In either instance, it will pull timing and boost.
 
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