Problem Reports

Subaru Forester

Report: Check Engine Light Due to Failed Knock Sensor

Subaru Forester Problem

22 Reports

Model Years Affected: 1998, 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010

Average Mileage: 134,513 mi (30,789 mi - 240,000 mi)

The Check Engine Light may illuminate because of a failed knock sensor. Although the sensor often tests okay, it can fail intermittently, while the vehicle is being driven.

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Report #1

Visitor, 1999 Subaru Forester, 30,789 mi

The check engine has come on twice in the past two weeks and the code read (knock). The engine has always made some noise from a piston slap but the light has never came on before. Now,I am wondering if I have an engine problem.

Answers anyone?

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Report #2

kayah, 1999 Subaru Forester, 240,000 mi

Enthusiast
knock sensor failed but good sensor havent fixed yet

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Report #3

elblann, 2001 Subaru Forester, 72,000 mi

Rookie
check engine light

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Report #4

triggz, 2002 Subaru Forester, 138,500 mi
Report #5

Visitor, 1999 Subaru Forester, 140,000 mi

Check engine light came on and the diagnostic code indicated bad knock sensor, located knock sensor and removed, founf it had a cracked housing. Replaced knock sensor and reset code. Now have 160,000 mile with no further problems.

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Report #6

Visitor, 2002 Subaru Forester, 175,000 mi
Report #7

duanednt, 1998 Subaru Forester, 190,856 mi

Rookie
My forester severly hesitates then suddenly speeds up my check engine light does report back the knock sensor, does the symptoms sounds related to the sensor?

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Report #8

Visitor, 1999 Subaru Forester, 134,500 mi
Report #9

Visitor, 1998 Subaru Forester, 197,000 mi

I had this same issue and reported it as well, but took it the shop and replaced the sensor as well as did a full tune up..All belts, Wires, Plugs and fuel filter and that fixed my check engine light as well as the A/T temp light

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Report #10

b_bus99, 2002 Subaru Forester, 61,000 mi

Enthusiast
CEL came on as knock sensor reading low. Changed knock sensor with a aftermaket (Bosch I think) and CEL went off and trouble code never came back.

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Report #11

Visitor, 1998 Subaru Forester, 100,000 mi

Check engine light was on and I discovered that it was the knock sensor. I replaced the sensor and even though I can hear slight detonation knocks, it is doing just fine after about a year.

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