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Hey guys, I was driving my car today and everything was fine and normal. I was picking up someone and when I got there, I had turned off my car for about 30 seconds. When I started the car back up, it wouldn't start. So I tried it again and it came on, but had a really rough idle and wanted to shut off from a lack of power or something. While it was running, there was a very loud clanking noise, like something was loose. That sound was very loud and apparent, so I couldn't tell exactly where it was coming from around the engine. I NEED HELP! I use this car for my job. I'm low on funds, but I obviously have to get it fixed, or I'll lose my job.
 

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Hey guys, I was driving my car today and everything was fine and normal. I was picking up someone and when I got there, I had turned off my car for about 30 seconds. When I started the car back up, it wouldn't start. So I tried it again and it came on, but had a really rough idle and wanted to shut off from a lack of power or something. While it was running, there was a very loud clanking noise, like something was loose. That sound was very loud and apparent, so I couldn't tell exactly where it was coming from around the engine. I NEED HELP! I use this car for my job. I'm low on funds, but I obviously have to get it fixed, or I'll lose my job.
Eeek... Well your description honestly sounds like you dropped a valve seat... Is it still clanking and making noise? Will it start now after being turned off? I'm hoping not but its the clanking that's worrying me. If it won't start at all after cooled then is say its definitely dropped a seat, which isn't going to be cheap and if its for work and you are low on funds then I'd recommend a used motor... But let's hope its not that... How long is the journey to your friends? Usually short distances seem to surround a dropped seat... I would pull the plugs and put a scope in each cylinder and look for debris or scarring before driving it personally... Better still pull a head and look for damage. Let us know if it starts when cool first...

Sent from my Autoguide app that doesn't show me what kind of car you drive, crashes twice on startup and in general keeps receiving updates that make the app even less helpful than the crappy previous version.
 

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That does not sound good at all. Can you localize the noise at all? Under the car, from under the hood, in the back? Where is the sound?
 

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Discussion Starter · #4 ·
Eeek... Well your description honestly sounds like you dropped a valve seat... Is it still clanking and making noise? Will it start now after being turned off? I'm hoping not but its the clanking that's worrying me. If it won't start at all after cooled then is say its definitely dropped a seat, which isn't going to be cheap and if its for work and you are low on funds then I'd recommend a used motor... But let's hope its not that... How long is the journey to your friends? Usually short distances seem to surround a dropped seat... I would pull the plugs and put a scope in each cylinder and look for debris or scarring before driving it personally... Better still pull a head and look for damage. Let us know if it starts when cool first...
Thanks for the reply, I will have to check tomorrow morning if it will start, as I had just gotten home a couple of hours ago. The drive is about a mile, but it started just fine when I left to pick her. I was leaving my work and it started up just fine. Would it cause the Engine not to fire when trying to start it? I mean it fired a few times after a bit, but it just wouldn't stay running. That is why it was having a rough idle before it just shut down completely. Kind of like a throttle body problem, but it couldn't be that because I just replaced it. Plus, it wouldn't explain the loud clanking noise coming from the Engine. That should answer MADDOG's question as well.

Thanks
 

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Rough idle has a few causes, most normally a dirty throttle body or bad EGR valve.

The clanking can be anything, including a loose fan, a failed accessory drive pulley or idler, a loose heat shield, etc...pretty much countless items external to the engine.

A clanking from within the engine, however, is much more serious. A "clank" is generally associated with an upper end problem, such as a broken valve spring or rocker arm. Since you were having a rough idle at the same time, I'd be leaning towards this sort of failure. A "knock" usually comes from deeper within the engine, possibly caused by a rod bearing or crank bearing.
 

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I'm gonna have to say that you have dropped a valve seat. As mentioned earlier, it's not a cheap fix. You can usually tell by inspectiong the plugs. If you have one with a closed gap, that will be the cylinder that dropped the seat.

You may also want to stop trying to crank it if it's making a clanking noise. You could be doing more damage to the engine.
 

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Assuming he did drop a valve seat, and there is no damage to the piston, couldn't he just replace the head on that side?
 

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Assuming he did drop a valve seat, and there is no damage to the piston, couldn't he just replace the head on that side?
Occasionally yes you can, but the seat has to go somewhere and as it drops inside the combustion chamber and makes friends with the piston usually its not a salvage with a new head job... ;) I would also recommend a new intake as you can't flush out the 5.7 one enough due to the runner design and putting it back together can prove fatal. He will know what needs to be done when the heads come off... Depending on what a scope shows first.

Now if the damage to the piston isn't bad he could pull the damaged one, see if it needs a light hone, clean up the piston and throw it back in for the time being. Might not be a weapon at the track but could be a solid runner for awhile!

Sent from my Autoguide app that doesn't show me what kind of car you drive, crashes twice on startup and in general keeps receiving updates that make the app even less helpful than the crappy previous version.
 

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Same thing happened to me. Driving perfect. Stopped. 10min later same exact issues. Dropped valve (from 2005 or so to like 2007) valve stem is manufactured a hair too small for head and the seat breaks. The noise, if with the rough idle not quite running and hard start, means you are having more problems. Do not drive it! It cost me almost 3000 to fix mine and since then took the time to learn most of the labor myself. I just recently had a new sound from my newly built engine and it took me an hour to remove intake and head from that side just today. The damage you have will be visible and you may want to do the labor yourself for teardown. Its an option to cut your cost down a lot. Consider this and then move forward according to what you find inside your budget.
 

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The damage you have will be visible and you may want to do the labor yourself for teardown. Its an option to cut your cost down a lot. Consider this and then move forward according to what you find inside your budget.
Me thinks the OP would have done something, one way or another, by now. These posts are from January.
 
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