knock knocking

C

canadian

Newbie
May 16, 2006
366
0
0
Victoria BC
To add to my long list of current problems, I have a knocking.
Here is the thread with my other problems:
http://www.supramania.com/forums/showthread.php?p=344165#post344165

I started the car up this afternoon after putting the belts back on. I am semi-familular with the injector TICK the 7MGTE makes...but when I turned it on this morning it was a knock.

I turned the car on, and let it idle around 5-600 RPM. Immediately there was a loud knocking sound.

How do I figure out 100% if its rod knock? Is rodknock linked to a BHG in any sort of way?

Also, while reading on rod knock I read someone suggested taking one injector clip out at a time to locate which cylinder the noise is coming from (and if the noise doesn't change, to confirm its not rod knock) How do I take the injector clips out? I will look in my haynes manual and the TSRM in the meantime.

Thanks
 
T

turbodriz

mk3 onwer
Feb 25, 2006
471
0
0
newyork....N.c
I believe that you can take along screw driver, while the car is running put your ear to the screwdriver and the screwdriver end to a runner (intake or exhaust). I believe that as you go to each runner, the one with the rd you'll hear in the screwdriver. But let one of the other guys confirm that.
 
Suprapowaz!(2)

Suprapowaz!(2)

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Apr 10, 2006
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Unplug #1 cylinder plug wire from coil. Knocking sound still there? No, plug it back in then go to #2 plug wire. Unplug it. Check for knocking. Plug it back in. And so on until you find the cylinder that the knocking goes away. When the knocking goes away then more than likely it's that cylinder.

When you take spark from the cylinder then you don't have combustion in there. It relieves the stress from the bottom end so the knocking goes away. It could be a rod knock, or come from the piston pin.

BTW, make sure all of your pulley bolts are tightend to spec. A wobbly pulley can sound like a rod knock.
 
P

pimptrizkit

thread killer
Dec 22, 2005
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vancouver Wa
on the injectors there's a small clip , studie it, and learn how to take them off, i use needle nose plyers most offten.. becareful though, if you are apply to much pressure while yankin, you'll break the locks.


and if you decide to pull the plug wires, i would suggest shuttin off the car.. being shocked isn't a fun way to learn.
 
johnathan1

johnathan1

Supra =
Aug 19, 2005
5,056
1
36
36
Downey, California, United States
pimptrizkit said:
on the injectors there's a small clip , studie it, and learn how to take them off, i use needle nose plyers most offten.. becareful though, if you are apply to much pressure while yankin, you'll break the locks.


and if you decide to pull the plug wires, i would suggest shuttin off the car.. being shocked isn't a fun way to learn.
Click to expand...

My exact thoughts.

Also, IIRC didn't you replace your head gasket some time ago? I have heard many times that if you do not drain all of the coolant from the block (not just the radiator) before you remove the head, that coolant will leak down into the oil passages and eventually cause rod knock. Did you change your oil several times immediately after the repair?
 
P

pimptrizkit

thread killer
Dec 22, 2005
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vancouver Wa
johnathan1 said:
My exact thoughts.

Also, IIRC didn't you replace your head gasket some time ago? I have heard many times that if you do not drain all of the coolant from the block (not just the radiator) before you remove the head, that coolant will leak down into the oil passages and eventually cause rod knock. Did you change your oil several times immediately after the repair?
Click to expand...


i did, but i think your askin candian. if he didn't, i sugest to stop driving the car imiditly(sp), and find another ride.. more damge = higher cost of repair..
 
SublimeSupra

SublimeSupra

Dreams of the Touge
Jan 17, 2006
170
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Largo,Fl
Becareful with those injector clips i broke all but one taking them off they broke like peanut brittle from 16yrs of heat.
 
S

Supra

New Member
May 11, 2005
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Rockford, IL
Suprapowaz!(2) said:
It could be a rod knock, or come from the piston pin.
Click to expand...

Have you ever seen or read about a failed wrist pin in a 3rd gen Supra? I see people post this as a possible problem from time to time, but have never ever witnessed a failed pin nor read anyone post that they had a broken/worn/cracked wrist pin.
 
C

canadian

Newbie
May 16, 2006
366
0
0
Victoria BC
I haven't replaced my head gasket ever. I purchased the car in July...
Maybe I will do the plugs instead of injector clips, I don't need to pay for more things like this, and I will shut off the car in between unplugging them.
I am not driving the car anymore... I am transfering insurance to my truck today or tomorrow... from beauty to beast :biglaugh:

So if the noise doesn't go away when I unplug the wires for each spark plug what could be the problem? Stupid question,is the coil underneath the plastic cover over the valve covers, or is it somewhere else. I looked for it and don't remember seeing it when I first bought the car...

Thanks!
 
Figit090

Figit090

Fastest mk3 GT4 1/4 mile!
Jan 7, 2006
1,835
1
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Humboldt County
i said a lot in my last post in your other thread. but i'll post here a bit because its more relavant here.

You can listen to the crankcase with a broomstick...poke around avoiding moving stuff...if you have room with that turbo mess ;)

i read also that you can listen underneath by putting it against the oil pan...if you have a reliable stand to start the car on.

when you heard the knock did you wait long before shutdown? its possible you have a problem like mine...maybe... and it might go away after a few seconds.

mechanic still sounds like a good idea though.
 
C

canadian

Newbie
May 16, 2006
366
0
0
Victoria BC
I will try the broomstick idea this weekend along with unplugging the injectors.
When it started up the FIRST time it was very loud and noticable. After that it wasn't near as loud each time we started it up... We didn't wait long to shut it off, to prevent more damage...
Thanks
 
Suprapowaz!(2)

Suprapowaz!(2)

New Member
Apr 10, 2006
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-Rich87Tx2 said:
Have you ever seen or read about a failed wrist pin in a 3rd gen Supra? I see people post this as a possible problem from time to time, but have never ever witnessed a failed pin nor read anyone post that they had a broken/worn/cracked wrist pin.
Click to expand...


No, I've never heard or seen a failed pin on a 7m. I suppose anything is possible though.
 
C

canadian

Newbie
May 16, 2006
366
0
0
Victoria BC
Spring and it's back to fixing.
In August I went through and unplugged each of the 6 cylinders one at a time. The fifth cylinder was the one that was knocking, when I pulled the plug it stopped knocking...
I have not started it up yet this year, maybe it will magically disapear!

If it is in fact number 5 knocking, is it a rod or what could it be?
Would it be safe for the engine to drive it to the toyota dealership to have them look at it to give it a final diagnostic? Or simular place...

Thanks
 
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