Thread: How screwed am i? UPDATE, WAS A BEARING, NOW WHAT?

First off, car is an 02 GTP, 103k miles. All stock with the exception of a CAI.

So about a week ago i noticed my car making a knocking sound. When the car is cold, and even up to like 170degrees there is no noise at all, but when the car reaches full operating temp there is a knocking sound that sounds something like a lifter tick. It is rhythmic to the rpms, but the sound doesn't get louder at higher rpms, just ticks/knocks faster. There is absolutely zero noticeable loss in power, the car runs excellent and idles smooth as silk. The knock is hardly noticeable from inside the car but is fairly noticeable from the outside. It is also just as loud underneath the car. What has me confused is how well the car runs and the fact that i find this odd to be having some sort of internal engine knocking with this low of miles and I've been very meticulous in maintaining it. I don't know exactly how long it has been knocking as like stated, from inside the car you wouldn't hear it if you weren't listening for it. I drive 80 miles a day and the engine hasn't even given the slightest hiccup. LIM gaskets were replaced at something like 90k miles so really don't think its a spun bearing or anything do to that, not to mention power loss should be considerable from that.

Here is a video but i'm not sure how the quality will be. The engine is already warmed up in this video, running at right around 180-190 degrees. We had record high temps here today and the car will run all day long with the AC on full blast without ever getting past 190. Kind of hard to hear in this video between the fans running and the intake sucking it has somewhat drowned out the noise. Also has an exhaust leak at the resonator which doesn't help either for sound quality. I'll try to get another video when it cools off a bit so its easier to hear.

GTP Ticking/Knocking - YouTube


Any thoughts would be greatly appreciated.


Edit: Better video. GTP Knocking #2 - YouTube

Take a video with it being revved a little bit.

did you start to notice this noise just after you put on the open cone?

because that sounds like every other 3800 out there.

try revving it up some, or drive it if you can hear it when driving. and take a new vid of it.

Will do, i was trying to rev it but the damn throttle cable was so hot from the heat outside baking on it i kept burning my hand trying to grab it. And no, the CAI has been on there since 2009, definitely not related. I'm well aware of the loud sucking sound from the CAI, but it appears it has drowned out the knocking too much for this video to be useful. I can hear it while driving, just barely, but i doubt it would be audible on video. I'll post back with another video in just a second.

Here is another video. This one is MUCH better. Knocking sound is very easy to hear in this one. The video is just now finishing uploading so if it doesn't work right away try reloading it in a minute or two.

GTP Knocking #2 - YouTube

you have a oil pressure gauge? if so has it changed at all? pressure drop.- bottom end

could be a cracked flex plate or the bottom end took a crap.

get the car in the air, take off the inspection plate, look for cracks, (hard to see) also start it with the cover off and get back under it and listen for it at the flex plate. it may get louder with the inspection cover off.

Sounds like rod knock to me.

No i don't, though i could get a hold of one. Definitely SOUNDS like it could be in the bottom end to me but what doesn't make sense to me is how well the car runs. Runs just as strong now as it ever has and 14.43, idles smooth, no vibration, nothing but this god awful sound. Listening to it again i notice it doesn't necessarily go rhythmic with the rpms, kind of rattles all over the place as the engine revs. Definitely think the flexplate is a good place to start. It's dark now but i'll take a look tomorrow. Just for my own education, does it make sense that the noise would be louder when the engine is hot if it is the flexplate, and if so, why?

Sounds like a an exhaust leak to me.

Is the oil free of sparkles?

OR I think its a pulley issue.

Try removing 1 belt at a time and see if the sound goes away.

A bottom end knock would have a real good tone to it.

when you were revving it and it was coming down in rpm's, i heard a banging that was off, from when going up, had that rod knock ring to it.



im used to sbc rod knocks, and know how they sound, every 3800 vid of a rod knock, well they squeal a lot, your sounds like what im used to hearing from a sbc. the rod slapping around the crank, or the piston hitting the head when it get bad enough. and that ringing tone when the rpm's are dropping. like a lighter tapping i guess.

still praying for a flex plate for ya tho.

edit, rod knocks are quiet till they warm up in the early stages of a bearing going bad. cold oil is thicker, warm oil is thinner.

Originally Posted by dsmuts

Sounds like rod knock to me.

Every engine i've ever known to have rod knock,
A.More destructive sounding, similar noise but more severe.
B.Extreme loss in power, usually from full power to nothing in a matter of a few miles. My engine has been doing this for at least 1,000 miles or so without the slightest indication of power loss.
C.The sound also gets more intense with time, this hasn't changed at all.
D.Smoke
E.Matched the RPM, upon listening closer, this doesn't exactly match rpm's

Not saying you are wrong, though i hope you are lol. Just trying to think everything out.

I doubt rod knock.

Do what I said and get back to us.

Originally Posted by Fivefingerdeathpunch

Sounds like a an exhaust leak to me.

Is the oil free of sparkles?

OR I think its a pulley issue.

Try removing 1 belt at a time and see if the sound goes away.

A bottom end knock would have a real good tone to it.

The oil looked good last time i changed it, but i have not changed it since noticing the noise. The dip stick is clean but i don't imagine much would be visible that way, would need to drain and look.

Definitely not an exhaust leak. Can tell its a something hitting something else type sound. Exhaust leaks are much more of a tick. I've had a few cars with exhaust manifold leaks, this sounds nothing like that. There IS an exhaust leak at the resonator that i need to address but that is very minor and secondary to this right now lol.

Also, as loud as it is under the car i doubt it's a pulley. Definitely something internal to the engine or echoing through the engine. Rod knock or flexplate sound most viable to me at this point.

oh you left out that its been there for a 1,000 miles lmao! then it cant be the bottom end, it would have let loose already on you.

back to the other suggestions. i think your safe. exhaust leak sounds like a reasonable repair job lol compared to a flex plate.

Still, I'd remove the belts and see if it goes away, you never know.

i agree, belt removal is free....and easy.

Sounds like my friends Caprice with a loose rocker.

I agree on the pulleys. I am all for what's free, just really don't think that's it.

Originally Posted by scottydoggs

oh you left out that its been there for a 1,000 miles lmao! then it cant be the bottom end, it would have let loose already on you.

back to the other suggestions. i think your safe. exhaust leak sounds like a reasonable repair job lol compared to a flex plate.

Sorry, i thought i included some sort of time frame in the original post, i may have forgot. First time i noticed this was a week or two ago, but like i said considering it can only barely be heard inside the car its possible its been significantly longer. I only happened to hear a slight noise while accelerating from a red light late one night when my radio was off. My girlfriend thought i was just hearing things but i when i pulled over and popped the hood sure enough i could hear something.

In any case, i drive it 80 miles a day 5 days a week to work and back and took it on a 300 mile round trip this past weekend. If it has been ~2 weeks or a little less that's easily 1,000 miles and it could be significantly longer. That's what has me baffled. The thing runs excellent. Never gets hot , idles perfect, no engine vibration, no power loss, no smoke, nothing but this horrid sound.

Little update here. Pulled the inspection cover off to check the flex plate. Had someone turn the motor over as i checked it very closely looking for even the slightest hairline crack...but found absolutely nothing. It looks perfectly fine from what i can tell. Took the belts off and still hear it. Tried to pin point the sound with a screw driver but was unsuccessful. It's difficult to even figure out which side of the motor its coming from but i'm fairly certain it is louder on the passenger side toward the rear but not even positive of that. Cannot for the life of me figure out what the hell it is. Still driving the car ~60 miles a day and even made a 100 mile trip over the weekend and the car still runs like a top.

Edit: Also checked the harmonic balancer. Not that either.