LEXUS SC430 P0325 Engine Knock Sensor
Thread Starter
10th Gear
Joined: Jan 2022
Posts: 13
Likes: 1
From: NY
LEXUS SC430 P0325 Engine Knock Sensor
Hello,
I just recently received a P0325 code, which I understand is a Bank 1 knock sensor. The engine lost much of its power. I took it to a local mechanic who could not hear a knock and suspected that the sensor itself or its harness may be faulty. I went through the hack where I connected the sensor from Bank 2 to the ECU. I used the pinout for the LS430 (which I assumed was the same). However, the check engine light with the same code came back. My concern is that if I have the actual knock sensors replaced, that the issue would still be there (and here in NY this repair seems to be very expensive). I only use premium and also used a fuel injector cleaner, which did not help. Any insight would be appreciated. Thanks!
I just recently received a P0325 code, which I understand is a Bank 1 knock sensor. The engine lost much of its power. I took it to a local mechanic who could not hear a knock and suspected that the sensor itself or its harness may be faulty. I went through the hack where I connected the sensor from Bank 2 to the ECU. I used the pinout for the LS430 (which I assumed was the same). However, the check engine light with the same code came back. My concern is that if I have the actual knock sensors replaced, that the issue would still be there (and here in NY this repair seems to be very expensive). I only use premium and also used a fuel injector cleaner, which did not help. Any insight would be appreciated. Thanks!
Pole Position
Joined: May 2016
Posts: 3,170
Likes: 672
From: AZ
I am not familiar with the Knock Sensor issue, since it is quite rare in the SC430. I do know @BON and a couple other guys changed theirs.
However an equal number of people thought it was the sensor and found out it wasn't
I would google Clublexus.com sc430 "knock sensor" P0235 and see what other people did to resolve the issue.
However an equal number of people thought it was the sensor and found out it wasn't
I would google Clublexus.com sc430 "knock sensor" P0235 and see what other people did to resolve the issue.
Thread Starter
10th Gear
Joined: Jan 2022
Posts: 13
Likes: 1
From: NY
My mechanic wants to charge me $1,100 to replace the knock sensors, which is difficult to swallow. Is this typical? Is there any way to troubleshoot to make sure it is the knock sensor? Thanks!
Pit Crew
Joined: Aug 2020
Posts: 132
Likes: 59
From: ca
as explained in post #4 of this thread, i dealt with this exact code for quite a long time.
https://www.clublexus.com/forums/sc4...l#post11263959
i paid $1,500, $675 for labor, the rest for parts and taxes. the big labor charge is because the top of the engine (intake manifold) has to come off and is apparently a PITA.
i changed both sensors even though only one was reporting an error. i also changed the starter since it was now accessible and my car has over 275k miles.
also, needed 2 new intake manifold gaskets.
other than timing belt replacement, this has been my biggest expense since i bought the car. no regrets, the car is an absolute joy to drive.
Thread Starter
10th Gear
Joined: Jan 2022
Posts: 13
Likes: 1
From: NY
it doesn't sound unreasonable to me, but i live in SF bay area and cost of living here is ?!@#$!.
as explained in post #4 of this thread, i dealt with this exact code for quite a long time.
https://www.clublexus.com/forums/sc4...l#post11263959
i paid $1,500, $675 for labor, the rest for parts and taxes. the big labor charge is because the top of the engine (intake manifold) has to come off and is apparently a PITA.
i changed both sensors even though only one was reporting an error. i also changed the starter since it was now accessible and my car has over 275k miles.
also, needed 2 new intake manifold gaskets.
other than timing belt replacement, this has been my biggest expense since i bought the car. no regrets, the car is an absolute joy to drive.
as explained in post #4 of this thread, i dealt with this exact code for quite a long time.
https://www.clublexus.com/forums/sc4...l#post11263959
i paid $1,500, $675 for labor, the rest for parts and taxes. the big labor charge is because the top of the engine (intake manifold) has to come off and is apparently a PITA.
i changed both sensors even though only one was reporting an error. i also changed the starter since it was now accessible and my car has over 275k miles.
also, needed 2 new intake manifold gaskets.
other than timing belt replacement, this has been my biggest expense since i bought the car. no regrets, the car is an absolute joy to drive.
Pit Crew
Joined: Aug 2020
Posts: 132
Likes: 59
From: ca
Thank you for your insight and sharing your experience. My main concern is that after going through the whole cost of replacing the sensors, the error code will come on again because it was not the culprit. I recently purchased this vehicle under the assumption/hope that these were bulletproof still at 110,000mi.
though many people say they never have had a knock sensor go bad, i wonder how may miles they have on their car? you got over 110K miles before your knock sensor went out. imo, that's not so bad. i got almost 274K miles out of my knock sensor. the code has not returned since i had them both changed.
7th Gear
Joined: Feb 2022
Posts: 7
Likes: 2
From: FL
Thank you for your insight and sharing your experience. My main concern is that after going through the whole cost of replacing the sensors, the error code will come on again because it was not the culprit. I recently purchased this vehicle under the assumption/hope that these were bulletproof still at 110,000mi.
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Thread Starter
10th Gear
Joined: Jan 2022
Posts: 13
Likes: 1
From: NY
The problem went away and I enjoy driving it, however, it still feels much more sluggish than my 2010 LS460, which I find surprising. My 1999 Boxster with 2 fewer cylinders feels much more quick, but I understand it is not a fair comparison. I hope this helps.
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Pole Position
Joined: Jan 2020
Posts: 2,738
Likes: 544
From: CA
Yes, a knock sensor detects pre-ignition. Once detected, the ECU retards the timing to eliminate the knock. However, if a sensor has failed, as evidenced by the codes, the vehicle won't pass smog. Too, if one inadvertently fills up with regular, and the knock sensors aren't working, then engine damage may result. So, based on these two possibilities, it seems like a reliability issue to me.
Lexus Test Driver
Joined: Dec 2014
Posts: 8,213
Likes: 952
From: Fl
I ended up replacing the knock sensor(s), which largely took care of the problem. At the same time, I also asked for the spark plugs to be replaced, timing belt, water pump, new engine mount, new air filter, synthetic oil change, and oxygen sensor cleaned. I don't remember exactly how much this cost me, but all this maintenance was well over $2K. I think the quote for the knock sensor was $1000 in NY using Lexus components.
The problem went away and I enjoy driving it, however, it still feels much more sluggish than my 2010 LS460, which I find surprising. My 1999 Boxster with 2 fewer cylinders feels much more quick, but I understand it is not a fair comparison. I hope this helps.
The problem went away and I enjoy driving it, however, it still feels much more sluggish than my 2010 LS460, which I find surprising. My 1999 Boxster with 2 fewer cylinders feels much more quick, but I understand it is not a fair comparison. I hope this helps.
if so, try this and report back
SC430 Accelerator Reset
1. Get in your car and insert key. (It doesn't matter if you close the door or not.)
2. Turn the key to the on (not start) position.
3. Press the gas pedal to the floor.
4. Hold the pedal to the floor for five seconds, then turn the key back to the "off" position
(don't remove the key), then release the gas pedal.
5. Wait 2 minutes.
6. Remove key.
Thread Starter
10th Gear
Joined: Jan 2022
Posts: 13
Likes: 1
From: NY
when you say sluggish, do you mean from a stop?
if so, try this and report back
SC430 Accelerator Reset
1. Get in your car and insert key. (It doesn't matter if you close the door or not.)
2. Turn the key to the on (not start) position.
3. Press the gas pedal to the floor.
4. Hold the pedal to the floor for five seconds, then turn the key back to the "off" position
(don't remove the key), then release the gas pedal.
5. Wait 2 minutes.
6. Remove key.
if so, try this and report back
SC430 Accelerator Reset
1. Get in your car and insert key. (It doesn't matter if you close the door or not.)
2. Turn the key to the on (not start) position.
3. Press the gas pedal to the floor.
4. Hold the pedal to the floor for five seconds, then turn the key back to the "off" position
(don't remove the key), then release the gas pedal.
5. Wait 2 minutes.
6. Remove key.
3rd Gear
Joined: Jan 2022
Posts: 3
Likes: 1
From: WA
Same same in Italy
Just had the PO325 come on, seems to be intermittent. I recently brought my 02 SC to Italy where I'm living now. If you're not familiar with the area, the roads are some of the worst I've experienced, and on the run flats I've failed to change it's a harsh harsh ride. My question is if anyone has experienced bad connections and if the roads were an issue? I'll jump into troubleshooting shortly. At first I was afraid i was getting crappy fuel but it turns out I've been running 95 or even 98 from a reliable brand here...