legacycentral bbs

My car recently started making a deep metallic banging noise. It's not the valves to the best of my knowledge. I'm hoping that the pistons aren't slamming up against the heads. Any other ideas on what this could be?

Rod bearings? Piston slap is when the pistons turn with the wrist pin as a pivot in the bore and the skirt hits the cylinder. If something caused them to hit the heads I can't imagine it would run long at all.

Steve

I think that was a typo and he meant the cylider walls.

I heard it a little the other day and it did sound like a mild slap. Could just be a miss too caused from a bad plug or plug wire (I hope) but Scott said it gets louder then when I heard it.

Definitely not valve lifter clatter or anything?

No, it's not vavle clatter, it's a deeper tone. My car engine sounds like a diesel when it gets hot.

I don't know my terminology very well but I was trying to describe what Steve did in better detail.

How does it run? Is it down on power? Really rough?

Steve

It has an erratic idle and sometimes it runs weak if I get on it but other than that noting really out of the ordinary. The idle can be pretty unstable at times and it seems like it might stall but it doesn't. Most of the time it's pretty strong.

How old are the wires? Really bad misfires can make it sound like it's coming unglued. First time I washed the engine bay I thought I did some serious damage.

Steve

The wires are relatively new. I bought some new ones and replaced the plugs this weekend. There's a couple other issues that may need looked at too first.

dup

Yeah, a lot of those cheap third-party plug wires for our cars have 90-degree bends at the coil pack side. Some of them have bends on all four wires, and some have bends on two of the four. In any case, you can still use them.

They're not very good wires to begin with, though... It's almost not worth buying any wires other than Magnecors.

auto or manual

If auto it could be your flexplate. Mine sounded like a diesel when mine broke.

Troy

Flex plate!! My gut is telling me that's a strong possibility. The previous owner replaced the flex plate after the owner before him tried to put a WRX tranny in, IIRC. Now, I'm not too knowledgeable about this stuff at this point so feel free to correct me. So maybe there's an ongoing issue there. After I listened to the noise for a while the other day I noticed that it seemed to travel around the engine so I don't think it's a problem with any one cylinder.

My flexplate is pretty noisy, too.. I'mma just wait until it goes out again so I can be all bummed about it, though..can't afford the downtime and there's no one to help me, anyway.
But if you've got the time and space, pull that sucker out.

Is there a way to check this without a complete tear down.

there is an inspection hole down and to the left of the throttle body. There may be a rubber plug in it. If you look down in there with a light and rotate the front crank bolt, you may be able to see a crack (I could when mine broke).

Troy

Thanks man, I'll get right on it.

vrg3 wrote:Yeah, a lot of those cheap third-party plug wires for our cars have 90-degree bends at the coil pack side. Some of them have bends on all four wires, and some have bends on two of the four. In any case, you can still use them.

They're not very good wires to begin with, though... It's almost not worth buying any wires other than Magnecors.

Yeah, I should buy some magnecores. They didn't have them at advanced so I just got the cheap ones for the sake of testing.