A couple of weeks ago, I finished my head gasket on my 1FZ-FE and everything is running great! Except for the knock sensor check engine light. We replaced the sensor before we re-assembled the engine, so we thought it was the connector. We ended up getting a new connector and replacing it, but the code still comes on, even after wiping the code. We wiped the code and drove it around, and it only came back on when we were accelerating up a hill. Definitely a power decrease. What do you guys think we should do next?
Code 52 1FZ FE
- Thread starter Carzan
- Start date
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- Thread starter
- #3
Both are connected. I think that maybe one of the sensors is bad. Is code 52 only the front sensor or both sensors?
Is it actually knocking tho? Check your spark plugs for coolant steam cleaning.
Have you put fresh fuel in the truck?
Have you put fresh fuel in the truck?
Looking at the FSM for a 1994 shows that code 52 is specific to the front knock sensor. Code 55 is specific to the rear knock sensor.
If you clear the code and it comes back then focus on the wiring to the sensor or the sensor itself.
If you clear the code and it comes back then focus on the wiring to the sensor or the sensor itself.
Fj80oregon
GOLD Star
did you use a OEM sensor? You could swap sensors and that would eliminate the wiring if it kicked the code 55.