d16z6 head "knocking"

[chris13]

ok so my car started knocking bout a week ago. it only does it when it been sitting for a while and i start it after its cooled off. i can also hear it when im at like 1/4 throttle just cruising. i think its in the head tho. anyways do yall think i should just replace the head or just rebuild it (going turbo after the first of the year). anyways any info will help.

[GSRteg®]

Sounds like me like there is something going on in the block.

[§treet_§peed]

yeah i mean if you head needs fixed or work the head tends to tick and cick not knock. and if i is the head you prolly just need a nice little head job

[EmminoDaGreat]

How many miles, does it have good oil pressure, has the oil pump been replaced if it has high mileage?

[SiRed94]

yeah sorry man but heads usually don't knock... i think you are probably having worn bearing/ clearance issues... report back with answers to ^^^ and we can probably let you know...

[Kaiser]

Just wanted to point out: Detonation (Knock) typically sounds like it's coming from the head because it's happening directly underneath it. The block absorbs more sound than the head typically does, so it channels up the explosions. Essentially there's no way to tell exactly what kind of sound you're hearing without a massive amount of time spent with your particular engine as they die. It could be bad bearings, pre-ignition/detonation, an issue with the valves, a loose spark plug, or as was the case in my '93 accord, it could be the sign of a cylinder starting to go bad. In my case the piston rings went bad in number 2 and caused blow-past which overheated the piston rod and burnt the crank bearings, melting the rod and causing it to warp and causing the bearings to seize and shear.

[SiRed94]

detonation is commonly heard as (pinging) but with a stock engine that has 9.2:1 compression i doubt this is the problem if the ignition/fuel parts are in an even halfway decent condition... an issue with the valves (aka bent etc) you would hear a tapping and it would be missing very bad throughout the power band... improperly adjusted valves would be tapping... out of curiosity... has it been stalling out when you brake suddenly or come to a stop lately?

[Kaiser]

Bent valve doesn't explain intermittance described by the OP.


it only does it when it been sitting for a while and i start it after its cooled off

Bent valves also make noise through the entire powerband. I agree that it's a distinct possibility, but I'd look for heat related ignition and fuel system issues first due to the intermittance. If you want to try and rule out detonation/pinging, then you can always try and fill up with premium and add octane booster. The added octane would, in most cases, cause the nature of the sound to change if it's at all related to detonation.

Actually you know what? I think I just ruled my own suggestion out. Detonation would occur more commonly when the engine has been warmed up for an extended period of time and not allowed to cool. I would start looking down the route of oil-starved moving components. Does the sound go away after the car has been running for a while? Oil-starvation can cause a "knocking" or "tapping" type of sound. Not sure why it wouldn't do it on cold startup as well though.

[Elbow]

Those springs in the head are old and like springing making it sounds like a louds noise bro happened to my car too.Just tihhten them.

[chris13]

car has 175000 miles on it (original EVERYTHING so far).
oil pressure is fine.
does it on cold start up (not on warm start) and is RPM dependant.
car doesnt stall on hard brakeing or anytime for that matter.

[TheProfiteer]

car has 175000 miles on it (original EVERYTHING so far).
oil pressure is fine.

does it on cold start up (not on warm start) and is RPM dependant.

car doesnt stall on hard brakeing or anytime for that matter.


around 2500-3500rpm right?


rodknock.

Take it to redline leave it there for about 30 seconds. That should take care if for ya. Oh yeah have a tow truck and a short block ready and take it to Mainstream.

Emmino does a great job =)

[Kaiser]

around 2500-3500rpm right?


rodknock.

Take it to redline leave it there for about 30 seconds. That should take care if for ya. Oh yeah have a tow truck and a short block ready and take it to Mainstream.

Emmino does a great job =)


That's pretty much what happened to my Accord. Was hoping he wasn't having the same problem.

:-\

[chris13]

ok thanks everyone for the help, if i can make it last till the first of the year ill be bringing it to mainstream to do a swap not sure what motor will be goin in yet but ill figure that one out soon enough, and again thanks everyone for the help

[SiRed94]

Bent valve doesn't explain intermittance described by the OP.



Bent valves also make noise through the entire powerband. I agree that it's a distinct possibility, but I'd look for heat related ignition and fuel system issues first due to the intermittance. If you want to try and rule out detonation/pinging, then you can always try and fill up with premium and add octane booster. The added octane would, in most cases, cause the nature of the sound to change if it's at all related to detonation.

Actually you know what? I think I just ruled my own suggestion out. Detonation would occur more commonly when the engine has been warmed up for an extended period of time and not allowed to cool. I would start looking down the route of oil-starved moving components. Does the sound go away after the car has been running for a while? Oil-starvation can cause a "knocking" or "tapping" type of sound. Not sure why it wouldn't do it on cold startup as well though.

no.. i was stating that your suggestion that it may be a valve issue was highly unlikely in the case of a bent valve... and no that is not a distinct possibility because the car would be missing throughout the powerband and that was not stated by him in his original post...

[Kaiser]

no.. i was stating that your suggestion that it may be a valve issue was highly unlikely in the case of a bent valve... and no that is not a distinct possibility because the car would be missing throughout the powerband and that was not stated by him in his original post...


O_o maybe you should just re-read this whole thread...what you said didn't make any sense. You're the one that suggested it was a bent valve, not me. I told you that it didn't make any sense. Now you've reversed all that. O_O

[Vteckidd]

Most likely its a rod knock.

Drain the oil into a clean pan an look for metal shavings with a magnet.

[SiRed94]

O_o maybe you should just re-read this whole thread...what you said didn't make any sense. You're the one that suggested it was a bent valve, not me. I told you that it didn't make any sense. Now you've reversed all that. O_O

no... i didnt.. you originally said that it could be a valve issue... and i was stating that they only type of knocking you would hear from SOHC VTEC head would be a bent valve because valve adjustment issues cause ticking... so nothing was reversed, and no... i told YOU that that didn't make any senses thats why i posted it in repsonse to your post originally...

[SiRed94]

Most likely its a rod knock.

Drain the oil into a clean pan an look for metal shavings with a magnet.

thank you...

[SiRed94]

but since the guy is done with this thread... so am I ... The End

[Vteckidd]

detonation is commonly heard as (pinging) but with a stock engine that has 9.2:1 compression i doubt this is the problem if the ignition/fuel parts are in an even halfway decent condition... an issue with the valves (aka bent etc) you would hear a tapping and it would be missing very bad throughout the power band... improperly adjusted valves would be tapping... out of curiosity... has it been stalling out when you brake suddenly or come to a stop lately?
:goodjob:

[chris13]

ok thanks everyone for the advice