What is function of knock sensor in toyota 4-runner

Asked by Fauxy Apr 16, 2015 at 08:49 AM about the 2005 Toyota 4Runner Limited V6 4WD

Question type: Maintenance & Repair

2005 4-Runner runs rough on start and then check engine light comes on with VSC
tracking lights. Wondering if it could be knock sensor and what is the function of a knock
sensor.After a few seconds to a minute, the super rough running engine smooths out but
light stays on. Someone also mentioned oxygen sensor.

3 Answers

103,735

Was just on a 4 runner forum. They say that if there is an error code, the VSC light will illuminate because the ECU shuts it down. Here is what the guy had to say: I want to share my experience with "Check VSC System Warning" that came on my dashboard about a week ago. I noticed that the warning Check VSC System came up while driving one day. I used my Obd2 scanner and ran the diagnosis and it came up with the code P0306, Cylinder 6 misfire detected and a check engine illuminated afterwards. Car would jerk while idling and would hesistate while speeding off. After careful study I narrowed the fault to possibly bad spark plugs. I learnt that the engine disables the VSC System when it starts loosing power. I went ahead to change the spark plugs. Now that is the interesting part; the plugs for the 2.4L 4cyl engine is different from the ones for the 3.5L 6cyl engine. The right plugs are FH20KR-11 and it was quite a challenge finding it. I got it and changed all the six plugs and cleared the codes. I drove for about 2km and the check engine light came up again together with the check VSC System warning. I got home and scanned the car again, this time around it came up with P0356, Ignition Coil 6 Primary/Secondary Circuit. I went ahead to replace the ignition coil on cylinder 6. After changing the ignition coil and clearing the codes i decided to test drive my car and it came back to life, full 268hp V6 power. It was quite an experience!! I also read where it could very well be a bad O2 sensor. That will cause the CEL to illuminate, thus disabling the VSC. I doubt it's a knock sensor issue. You should hear engine noise and it should be running quite bad. Like getting misfire codes.

4 people found this helpful.

Excellent explanation Reelin68. A knock sensor is a sort of microphone, that 'listens' for when detonation happens inside a cylinder and aids the ECU in ignition timing. The fault code is P0325 ..or P0326 bank one or a single bank engine, P0332 for bank 2 in a V6 Toyota

3 people found this helpful.
10

My 04 4runner just did something similar, I went to pull off from the stop sign and it made a loud noise the check engine light came on the VSC light came on and it started knocking really bad. Any ideas?

1 people found this helpful.

Your Answer:

4Runner

Looking for a Used 4Runner in your area?

CarGurus has 309 nationwide 4Runner listings starting at $9,700.

Postal Code:

CarGurus Experts

  • #1
    Papaobewon
    Reputation
    5,810
  • #2
    Kurt Burton
    Reputation
    2,610
  • #3
    azurro
    Reputation
    1,680
View All

Find great deals from top-rated dealers

Search

Related Models For Sale

Used Toyota Tacoma
57 Great Deals out of 1,080 listings starting at $8,708
Used Toyota Highlander
32 Great Deals out of 737 listings starting at $2,495
Used Toyota Land Cruiser
98 listings starting at $33,990
Used Lexus GX
4 Great Deals out of 54 listings starting at $13,800
Used Toyota Tundra
34 Great Deals out of 1,190 listings starting at $8,500
Used Toyota Sequoia
4 Great Deals out of 72 listings starting at $16,489
Used Toyota RAV4
100 Great Deals out of 2,089 listings starting at $3,888
Used Ford F-150
321 Great Deals out of 15,103 listings starting at $1,712
Used Chevrolet Tahoe
20 Great Deals out of 904 listings starting at $11,900
Used Toyota Camry
48 Great Deals out of 979 listings starting at $2,212
Used Jeep Wrangler
146 Great Deals out of 5,076 listings starting at $5,450
Used Honda Pilot
45 Great Deals out of 1,256 listings starting at $4,495
Used Chevrolet Silverado 1500
195 Great Deals out of 5,967 listings starting at $2,975
Used Jeep Grand Cherokee
122 Great Deals out of 3,221 listings starting at $4,995

Content submitted by Users is not endorsed by CarGurus, does not express the opinions of CarGurus, and should not be considered reviewed, screened, or approved by CarGurus. Please refer to CarGurus Terms of Use. Content will be removed if CarGurus becomes aware that it violates our policies.