Engine knock

[lewis.young64]

I have a 89 Supra with 7MGE that has a knocking nose. I pulled the plug wires one at a time and the knocking did not stop. any ideas? top end, bottom end, knock sensor, water pump. Thanks

[SupraTuned]

More than likely, you have an engine that has been beat on too hard for too long. I am guessing if it is an audible knock inside of the car, it is probably rod knock which = engine rebuild. You will have to replace the rods and pistons. Of course, this brings up the potential to make the engine stronger, say, with forged internals....but hey, have somebody who knows a lot about cars troubleshoot.

[Jeeves]

Here's a handy guide that Google turned up quickly, I make no statement that it's 100% accurate:

http://www.aa1car.com/library/engine_noise.htm

I would say though that it does sound like Rod Knock which is a well known condition in our cars often caused by running them on low oil.

@SupraTuned, it has little to do with the pistons and rods. They just take the beating after the damage has been done. Really it has more to do with the bearings on the crank and the damage that's been done there. Those will have to be replaced as will machine work have to be done or possibly replacing/machining of a new crank. All around it just means an expensive rebuild procedure. It's not just a simple "Replace the sensor, keep going".

[SuLLiVaN88]

exactly sounds like rod knock!

time for a rebuild.. dont know what your money situation is..
but ill let you know that my brother's 86.5 supra has had rod knock for 6 months lol
he just puts a little thicker oil in it and doesnt get over 3000 rpm (most of the time) and it really hasnt gotten worse.. he does not want to put money into it because he is almost done building his 90 supra

[SupraTuned]

@jeeves: yeah I worded that wrong. I meant to say that this brings up the opportunity to replace the internals. Rod knock is usually because the bearings, crank or both are worn to a fatal point and are slapping around. My bad, but yeah, that's all I can think of that could be wrong with the car short of hearing it myself.