P0327 & P0332 Knock sensor Bank 1&2 Circuit low input Topic is solved

[- Pete -]

I've got a weird one here.
This is on our 04V70 AWD.

With my ELM327, using Torque pro, I pulled up P0327 & P0332 just this evening.

I've been searching & I can find only one Volvo-specific mention of this code & it was on Swedespeed & the thread had zero replies.

I recently had the transmission out of it to replace the flywheel. Just prior to that I had done the entire PCV system, dropped the oil pan, replaced pickup tube, seals etc...

Since replacing the flywheel I really haven't driven the car much, until the last couple days. That's when I noticed how much of a turd it seems to be! That brings us to now - when I scanned for codes & the knock sensor codes were brought to light.

Running/driving, WOT the throttle position rarely goes above 38.4% (anywhere under redline), which I suppose makes sense if it has de-tuned itself.
Now boost psi, I've never really understood how these cars are calculating it, or how it is being interpreted via ELM327 readers, but the numbers reported via ELM327/Torque are obviously something other than what the throttle body is actually seeing in PSI. After first & second gear, it's showing a pretty consistent 15.7-8 WOT (probably more like 1-3 psi real world). Another example of it de-tuning.


Anyhow, any of you guru's have any ideas where to start?

I do not have DICE/VIDA.

[- Pete -]

The car did sit unused for ~ 8 months with a full tank of gas in it, prior to me changing the flywheel.

I'm pretty particular about where we fill the vehicles up, but still, even the "best" available 93 ethanol will have deteriorated & have a layer of water in it in short order.

Hoping it just needs the old fuel run out of it, but hoping has always led to great let-downs in my (Volvo) experience!

I'll check compression tomorrow as a rudimentary test.

Worst case, it's that #5 rod bearing. Looked good when I inspected it less than 1k miles ago.

[abscate]

Those are knock sensor codes and are probably spurious. Did you clear them And see if they come back?

Signal voltage high for front and rear , respectively.

[jimmy57]

Check to be sure the two knocks sensor connector is plugged in. It leads down and plugs into connector on the plastic harness enclosure that is in turned attached to subframe. The knock sensors are not able to be checked by continuity so the ECM expects to see a minimal voltage spike from both when engine load and speed reaches certain values. Absent that you get the low signal codes. The knock sensors on that year model have leads made onto the sensors and they go to the one connector.

[- Pete -]

It was exactly as Jimmy57 suggested - unplugged knock sensors plug at their subframe connection. Jimmy, thank you!

Gotta love the simple fixes! It is so rare I get one of these, it's truly more like never.

I tried to take a picture, but with my 3.5-year old in the lighting department we didn't get the shot.

You know, this could be an excellent way to "govern" your newly-driving teen's wear tear on the car.

Zero CEL's produced. I'll have to remember this in ~12 years when she starts driving = unplug knock sensors!