Knock sensor went off, code 34, help

[Motiv']

So my check engine light came on last week and i've driven it quite a bit since i thought it was nothing, as last time it was code 55, 'no problems'. Turns out this time it's code 34 - knock sensor, and code 103 - park/neutral switch, wahtever that is. So i figure code 103 is nothing major, worth fixing? I found this out while changing my oil with my buddy, there is a noticable knocking in the head, we both thought it sounds like the cams, or a lifter, something small rattling around in the front of the engine. Any ideas of what it could be, cause god damn that's gonna be expensive to fix. How hard is it to take the valve cover off and diagnose with little experience?

cheers

[Hijacker]

Sounds like it's time for your timing chain to be serviced

[steamer1227]

you said that you hear a rattle from the front of the motor...is a rattle or like a scratching sound.. if scratching=then its actually a recall that if it hasnt been done yet then should be prob....all it is, is the timing chain guides. on the top of the motor and along the side...the recall says actually to remove them and leave them off due to timing chain to scratch them...

maybe could help...

[onosqv]

Sounds like it's time for your timing chain to be serviced

So when the ecu spits code 34, it means to "fix the knock" as opposed to "knock sensor is bad"?

[stlwaco]

So when the ecu spits code 34, it means to "fix the knock" as opposed to "knock sensor is bad"?

No. It could be both. The knock sensor picks up audio signal from the engine and reports it to the ecu. If the ecu determines there to be a knock, the check engine light will illuminate. The ecu will also trigger the check engine light if it detects a circiut malfuntion. That could be the sensor, wiring, or even the ecu.

[djmatt79]

No. It could be both. The knock sensor picks up audio signal from the engine and reports it to the ecu. If the ecu determines there to be a knock, the check engine light will illuminate. The ecu will also trigger the check engine light if it detects a circiut malfuntion. That could be the sensor, wiring, or even the ecu.

now... if thats a hard code... then how come when i erase it b4 i start my engine it doesn't come back during my ride? check engine light always illuminates when i shut off and start the car.

any ideas?

[MarkRipoll]

try to fix code 103 first before anything, i know that whenever in the past a code has gone on, the knock sensor code came on with it, then when i fixed the problem the knock sensor code went off with it too.

[MYFREE95,240SX]

well if you read the fsm the knock sensor will not throw the cel on it will be stored in the comp. my rear o2 went and my cel light came on and it pulled a knock sensor code and a rear o2 it says this specifically in the fsm that 34 will not throw a cel.

[rms13Mike]

well if you read the fsm the knock sensor will not throw the cel on it will be stored in the comp. my rear o2 went and my cel light came on and it pulled a knock sensor code and a rear o2 it says this specifically in the fsm that 34 will not throw a cel.

sorry to bring this back up but im having similar pro but mine is 32:EGR and 34: Detonation sensor circuit. ooh and my car is a 92 btw. but is it similar and true that knock sensor wont throw a CEL? so my only problem is the EGR? thanks in advance!