HELP 1995 LS400: Did i bend valve/s?
#16
Moderator
Hey guys, what will happen if one of the wire of the knock sensor is cut?
I saw videos on youtube that if the knock sensor is bad it will retard the timing.
i asked becuase the wires from my knock sensors are brittle and have a little bit of wire exposed. I rewrapped them with electrical tape with just one hand since they are under the intake manifold... kind of half-*** job and i dont know if i snapped a wire.
I saw videos on youtube that if the knock sensor is bad it will retard the timing.
i asked becuase the wires from my knock sensors are brittle and have a little bit of wire exposed. I rewrapped them with electrical tape with just one hand since they are under the intake manifold... kind of half-*** job and i dont know if i snapped a wire.
The knock sensor generates the voltage when the engine knocks. No knocking generates no voltage. When no voltage is there, the ECU judges that the fire timing is good or retard depending on conditions and it tries to advance the timing some until the knocking voltage is obtained and then retards some to decide the correct timing. The short circuited sensor or wires can't send any voltage to the ECU. Now you know the answer.
#17
How did we get from a bent valve to a knock sensor? And making a noise and what sounds like a misfire too?
The comp test or leak test is next. I'm onboard with the bent valve that is what will allow the extra valve lash, and cause the miss.
The comp test or leak test is next. I'm onboard with the bent valve that is what will allow the extra valve lash, and cause the miss.
Last edited by dicer; 02-05-15 at 03:47 AM.
#18
Both cylinder mentioned above is at 0 TDC and here are the results:
Cylinder #1 I checked hissing/leaking noise from exhaust pipe, intake manifold, crankcase, and exhaust pipe, none of them so this one is good.
Cylinder #6 hissing/leaking sound I can hear right at the injectors, I can smell fuel too. There is no leak I can hear from the exhaust pipe. Notice the amount of leak on the gauge.
#19
I will be taking the passenger side head off, i have a question though, am i able to use any 1UZFE TSRM on a interference 1995 model i have?
The timing belt replacement procedure on 1995/1996/1997 is different from 1991-1994, I was wondering if putting the head back will be the same as pre 95 ones.
The timing belt replacement procedure on 1995/1996/1997 is different from 1991-1994, I was wondering if putting the head back will be the same as pre 95 ones.
#20
I wouldn't advise disabling the knock sensor.... for starters, you will have a check engine light, unless you know some magical way to fool the computer... and 2: If there is no sort of knock control or detection, under the right circumstances, a pre-detonation can cause massive amounts of damage to internal engine components.
#21
Could this be just bad timing on the passenger side cam? Maybe jumped one tooth? Would this be the result of ticking sound just like in the video?
When the crankshaft pulley is at 0 TDC, both cam gears aligned to the metal back plate. Again im just speculating.
When the crankshaft pulley is at 0 TDC, both cam gears aligned to the metal back plate. Again im just speculating.
#22
One tooth off
I would be very surprised if having the valve train off by one tooth would cause any leakage @ TDC. OTOH, I would suspect that a bent valve would show MORE leakage than what you are seeing. You may just have a little debris under the intake valve(s) seats, and that's difficult to diagnose. Sometimes a good carbon cleaner into the throttle body, and a few moments of WOT on the hi way can cure that. It's worth a try.
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Tappy
LS - 1st and 2nd Gen (1990-2000)
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09-16-18 09:21 PM