Knock troubleshoot.

[Dred]

I have knock in my car, then it goes away.
Lets say, I keep the car revved at 2k rpm, i hear knock. Knock goes away in a few seconds ( ECU adjusts timing). I let go of gas for a few seconds, bring it back up to 2k RPM, same scenario.

I was fkn around with my timing a while back, using the TPS (not sure but the round thing on the top left corner of head) and turned it up all the way cause i didn't hear knock. The reason i didn't hear it was prolly cause the ecu retarted the timing for the time being. Could this be it, should I just try to turn my timing back down to whatever is good. P.S. dont have a pocket logger yet. Mod free car as well.

 

[ACKERSON]

You should not be messing with anything on your car, you have absolutely no idea what you are doing. You need to take it to a mechanic as soon as possible or you are going to have some serious issues.

 

[Dred]

You should not be messing with anything on your car, you have absolutely no idea what you are doing. You need to take it to a mechanic as soon as possible or you are going to have some serious issues.

I know alot about what I'm doing, if this is your answer, it's no answer at all. If I didn't know what I was oding I wouldn't be asking any questions here nor would I attempt to troubleshoot anything myself if I wanted to take it to a mechanic. Most mechanics don't know half the things about DSMs that I do.

 

[Burnett03]

I know alot about what I'm doing, if this is your answer, it's no answer at all. If I didn't know what I was oding I wouldn't be asking any questions here nor would I attempt to troubleshoot anything myself if I wanted to take it to a mechanic. Most mechanics don't know half the things about DSMs that I do.

how about a real, non smart ass comment.. Ill try..

1st) Check your base timing, check the vfaq if you dont know how. Make sure its at 5BTDC
2nd) What are your mods, turbo, intercooler, injectors pump, etc

The smart ass comments around here are getting old. This poor guy is trying to learn on his own and not pay money to a mechanic and you must write some comment like that.. Its stupid.

How are you knowing you are knocking without a pocketlogger? Knocking sounds of the engine, isnt the same as knock that the knock sensor reads, although it can trip the knock sensor. Check the timing, ground the ISC and turn all the acc. off and set it. (with cas) And leave it.

 

[psychlow]

I agree that posts like the first reply are worthless and help no one.

(He mentioned that the car has no mods.)

What is the knock you're getting sound like? If it sounds like thumping or a metallic thud, it's not detonation.

If it sounds like marbles or BBs bouncing around inside a can, it is probably detonation.

The "TPS" you were messing with is actually your CAS, or Camshaft Angle Sensor. You need to make sure that this is set correctly, as the last poster suggested, at 5* BTDC. THIS IS VERY IMPORTANT for your engine.

I hate to be the bearer of bad news, but if you have a metallic thumping/knocking sound that gets louder as you accelerate the engine, but quiets down as the engine speed steadies, you probably have a spun rod bearing, especially if the sound is loudest when you first start the car when cold.

 

[Dred]

Thank you both, real good answers.
I turned down my timing and everything is tip-top now.

Also, you know sometimes when you start after a cold night and it sounds like your valves are going to pop through the valve cover, fixed that too. Who woulda thunk it

But yes, my rod bearing are messed, I'm gettin those and a lot of other things that have gone bad in the nearest future.

 

[ACKERSON]

I wasn't being a smartass. Anybody that just grabs their tps (cas) and starts turning it because they think their engine is detonating (or rod knocking in this case) should not be working on their own car.

No timing light (to check and set ignition timing), no datalogger ( to determine if the engine is detonating or to set timing), I'm assuming that a jumper wire was not connected to the timing adjustment plug since he didn't mention it. Confusing the tps with the cas, I guess anybody could make that mistake. Then not being able to tell the difference between rod knock and detonation. I guess the next logical step would be to turn the cas to make the rod knock go away. Makes sense to me.

I understand he is trying to learn, but just jumping in and making adjustments without knowing the consequences, or even the source of the problem, is not the way to do it. Obviously turning the cas all the way in one direction could cause irreversible engine damage, which is why I said he should not be working on his car. The whole point of working on your own car is to fix it, not to break it.