What Does Code P0325 Mean?
- P0325 definition: Knock Sensor 1 Circuit Malfunction (Bank 1)
- Issue Severity: LOW – Continued driving for a short period of time is okay
- Repair Urgency: Get this fixed within the next month to prevent damage to your engine and emission system.
- Diagnosis: There are no driveability concerns with trouble code P0325. However, along with all Diagnostic Trouble Codes, there should be a sense of haste in getting this repaired so that there is no further damage to the engine.
Knock sensors are solely used for the purpose of sensing when your engine is “knocking,” or sensing when the air/fuel mixture combusts prematurely. This delivers less power and can also damage the engine if prolonged. When the engine “knocks” there is also an excessive amount of NOx that is released. When trouble code P0325 is set, this means that knock sensor 1 in bank 1 is not operating properly.
There are many potential causes of code P0325.
- Engine is running excessively lean
- Faulty or damaged knock sensor wiring
- Faulty sensor 1 Bank 1 knock sensor
- Engine coolant system fault
- Check Engine Light
- Loss of engine power
- No noticeable drivability issues
How Do I Fix Code P0325?
With a knock sensor fault, the first step is to get it diagnosed to figure out what is causing the problem.
If your vehicle has this fault and you’re not comfortable diagnosing this issue at home, we recommend finding a RepairPal certified shop nearby to pinpoint the problem and give an accurate estimate for repairs.
These shops can not only help you figure out what’s going wrong before you waste time and money on the wrong parts, but they also offer a minimum 12-month, 12,000-mile warranty and stand behind all their estimates with guaranteed fair pricing.
How Much Does It Cost to Fix Code P0325?
P0325 can be caused by anything from damaged wiring to a bad knock sensor to an overheating engine. It’s impossible to give an accurate estimate without properly diagnosing the issue first.
If you take your car to a shop for diagnosis, most shops will start with an hour of “diag time” (the time spent in labor diagnosing your specific issue). Depending on the shop’s labor rate, this typically costs somewhere between $75-$150. Many, if not most, shops will apply this diagnosis fee to any required repairs if you have them perform the repairs for you. From there, a shop will be able to give you an accurate estimate for repairs to fix your P0325 code.
Possible Repair Costs for P0325
For error code P0325, one or more of the below repairs may be needed to solve the underlying issue. For each possible repair, the estimated cost of repair includes the cost of the relevant parts and the cost of labor required to make the repair.
- Knock sensor: $297 to $381
- Knock sensor harness: $14 to $66
- Temperature sensor: $392 to $427
DIY Steps to Diagnose Code P0325
Engine code P0325 could be caused by a number of things, including damaged wiring, a bad knock sensor, or an overheating engine. If you’d like to try to fix code P0325 at home without throwing money at parts, you’ll want to follow the steps below for proper diagnosis. Keep in mind this is an intermediate-level diagnosis and repair and not recommended for beginners. Diagnosis requires more specialized equipment beyond what the FIXD Sensor can provide and it can be a time and labor-intensive process for inexperienced DIYers.
DIY difficulty level: Intermediate
This repair requires mechanical knowledge and is not recommended for beginners.
Tools/parts needed (our top picks from Amazon):
- Live Data (Found on FIXD App with Sensor)
STEP 1: USE FIXD TO ENSURE NO OTHER ENGINE CODES ARE PRESENT.
Use FIXD to scan your vehicle to verify P0325 is the only code present. If not, make a note of the additional codes, as they help diagnose the problem.
STEP 2: CLEAR CODES, DO A ROAD TEST.
Clear the fault codes with your FIXD sensor, then go for a drive to see if the problem comes back. Include some uphills and hard acceleration, which are both conditions that would cause engine knock. If the Check Engine Light comes back on, scan the codes again to see if they are the same or different than the first time.
STEP 3: CHECK KNOCK SENSOR SIGNAL.
Using FIXD Live Data, check the knock sensor voltage to ensure that it is within the specified range. If it is not, or if there is no signal at all, skip to Step 5.
STEP 4: CHECK TEMPERATURE SENSOR SIGNAL.
Using FIXD Live Data, check the temperature sensor voltage to ensure that it is within the specified range. If it is not, the temperature sensor may be sending false readings to the PCM, which could cause a lean running condition and engine knock. Check the temperature sensor and wiring and replace if necessary.
STEP 5: INSPECT KNOCK SENSOR WIRING.
Visually inspect the wiring around the knock sensor for disconnected or damaged wires.
STEP 6: REPLACE KNOCK SENSOR AND HARNESS.
If the conclusion is that the knock sensor needs to be replaced, then it is often recommended to replace not only the sensor but the knock harness as well.
Common P0325 Diagnosis Mistakes
There are times when the engine coolant system is the issue and replacing the knock sensor immediately will not make the Check Engine Light turn off.
Still Need Help Fixing Code P0325?
If you’ve followed the steps above and are still experiencing check engine code P0325, please contact the FIXD Mechanic Hotline if you’re a FIXD Premium subscriber or find a RepairPal certified shop near you to get the right repairs at a fair price.
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