knocking sound, from valves (possibly)

**civenegas85** · 02-28-2010, 09:59 AM

Hi guys, I need some thread support on this one.

I'm getting a ticking sound from what sounds like the heads. I have an 05 GTO. I spoke to a mechanic over the phone and he said it's possibly a cracked valve spring. If I were to decribe the sound, it sounds like a tapping from the rockers on either a rod or spring. It's very faint at idle and sounds louder when the revs are dropping....I heard it for the first time two days ago, car is grounded now. When I removed the covers, the sound was louder. any one have this issue before?? what should i do???

What side is bank1? or 2?

Any info woulde be appreciated.

Loz from Texas

**Hi-Po** · 02-28-2010, 10:02 AM

Manual car? Did you over rev recently? You said you did remove the valve covers? No broken springs? Next easier thing to do would be to pull the pushrods and roll them on a flat surface to check for a bent rods.

**35th-ANV-SS** · 02-28-2010, 10:12 AM

Pretty sure Bank 1 is always the side of the engine with cylinder #1. For our cars, this is the left side (1,3,5,7)

**civenegas85** · 02-28-2010, 10:30 AM

I did over rev recently....hm..

I removed the last two rockers and rods but they looked pretty straight. Maybe i should just roll them. spring doesnt look bad, but not sure how to check. Bank 1 is left side from inside or looking at car from front?

**35th-ANV-SS** · 02-28-2010, 10:31 AM

looking at it from the front.

**civenegas85** · 02-28-2010, 10:34 AM

Thanks for the bank info. I've been getting P0237 code for bank one, but this was there for a while. Knock sensor (low voltage). Just recently I started getting an 02 sensor reading also..... more info for diagnosis.

**civenegas85** · 02-28-2010, 10:38 AM

What would fail first, valve, valve spring, or push rod

**35th-ANV-SS** · 02-28-2010, 10:39 AM

Originally Posted by civenegas85

What would fail first, valve, valve spring, or push rod

If over rev'd I would think a push rod would bend first, if stock. They are supposed to be the weakest link. Could be wrong though.

**civenegas85** · 02-28-2010, 10:41 AM

I'll double check them again tonight....anyone know the torque settings for rocker screws?

**Hi-Po** · 02-28-2010, 10:46 AM

Originally Posted by civenegas85

I did over rev recently....hm..

I removed the last two rockers and rods but they looked pretty straight. Maybe i should just roll them. spring doesnt look bad, but not sure how to check. Bank 1 is left side from inside or looking at car from front?

I would start looking there. Pushrods will make this noise, and are easy to bend [stock].

Originally Posted by civenegas85

What would fail first, valve, valve spring, or push rod

Stock, A pushrod will bend first. Some guys leave stockers in there for a fail safe. Valve spring shouldn't fail if set up correctly and used in the correct application.

Originally Posted by civenegas85

I'll double check them again tonight....anyone know the torque settings for rocker screws?

22 ft/lbs

Roll them on a piece of flat glass. If they are really bent, you should be able to notice by just looking at them.

Edit: Pull the fuel pump fuse and disconnect the two main coil connectors. Turn the engine over a few times and then recheck your rocker arm torque.

**civenegas85** · 02-28-2010, 01:56 PM

Good info......what would be the part number for the pushrods. Where can I get them fast? and Where can I get the better price?

**Hi-Po** · 02-28-2010, 02:04 PM

Mark at WWW.kyspeed.com can get them fast and cheap. PM him at marksls1ta. He get you you squared away.

**civenegas85** · 02-28-2010, 02:20 PM

Should I keep the car grounded? or can I drive without pushing it?

**civenegas85** · 02-28-2010, 04:38 PM

I'm gonna keep it grounded, plus i went to kyspeed.com and there isnt much regarding GTO parts, should I just look under Camaro parts?

**Hi-Po** · 02-28-2010, 04:49 PM

Send him a PM here on this board. User name is

Marksls1ta

**civenegas85** · 03-01-2010, 12:15 PM

I rolled the push rods today and they are straight. I just called my local GM Dealership and I just ordered 2 valve springs. I'll pick them up tomorrow. I know a few things for sure. It is not the rods, or the rockers. Next could be the valve or valve spring.

To make sure it wasnt the rockers or the rods I actually switched the back two with the front two. I switched the rockers and the rods. When I put them back together and started it up again. The sound still came from the back (where sound originally came from). All the rods are the same size, 7.400" in length.

Anyone have a how to on valve spring replacement?

I know my way around an engine so I know I can do it myself, but it would save the time from learning as I go along.

Thanks guys.....

**Hi-Po** · 03-01-2010, 01:13 PM

Originally Posted by civenegas85

I rolled the push rods today and they are straight. I just called my local GM Dealership and I just ordered 2 valve springs. I'll pick them up tomorrow. I know a few things for sure. It is not the rods, or the rockers. Next could be the valve or valve spring.

To make sure it wasnt the rockers or the rods I actually switched the back two with the front two. I switched the rockers and the rods. When I put them back together and started it up again. The sound still came from the back (where sound originally came from). All the rods are the same size, 7.400" in length.

Anyone have a how to on valve spring replacement?

I know my way around an engine so I know I can do it myself, but it would save the time from learning as I go along.

Thanks guys.....

I just made one for you, and others

How to replace Valve Springs

**civenegas85** · 03-01-2010, 02:19 PM

Thanks, just looked it over and it does not look like rocket science, just gotta have the right tools and patience. I love my car so I'm ready to put in the time.

Pix look great too, easy to understand. Now I just need the parts and tools. Any suggestions incase it's the valve that I need to replace? I may have to remove the head completely huh.....

**Hi-Po** · 03-01-2010, 02:44 PM

Nope, its really easy

Pictures help everyone feel confident going into an install.

I don't know why it would be a valve. But yes, you will have to remove the head. Gonna have to remove the head to even look at the valve. But the chances of it being a valve are pretty slim unless on that over rev situation they hit the piston. Being stock pushrods, that's not likely to happen at all.

**civenegas85** · 03-01-2010, 03:02 PM

How can I be certain its a broken spring or valve? What should I look for. With the valve cover off, the springs are very difficult to move, could a small crack make the tension be too low?