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Old 03-21-2008, 10:54 AM
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Default engine noise

Just picked up a 2001 Range Rover. There is a loud popping noise while the engine is running. It seems to be coming from the pass. side rear of the engine compartment or maybe even underneath the car. There are no oil, fuel, water leaks. Any guesses??
 
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Old 03-21-2008, 11:16 AM
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Default RE: engine noise

So have you opened the hood to try and locate the noise?
If not do so, then get back to us with more specific information and let's see if we can help you.
 
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Old 03-21-2008, 11:33 AM
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Default RE: engine noise

I have had the hood open. It is a popping and not a constant rumbling. Like if the y-pipe was split there would be a constant rumble from the exhaust leak. I thought maybe air tube or exhaust mainfold because the sound seems specific to each exhaust stroke of a cyl. The exhaust manifold has a shield rivited to it so I cannot really get a good look without removing it.

I thought perhaps someone had run into this beofre and could narrow the scope of my search.
 
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Old 03-23-2008, 06:36 PM
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Default RE: engine noise

Yeah most possible cause your exaust gaskets on the downpipe took a poop easy way to see is either wait untile its super cold and start it and run your hands around it and you should feel the air if its cracked or leaking or if its hot put a mirror around the area and if it fogs up then you have a leak or a crack. most of the time the gaskets go bad
 
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Old 04-08-2008, 08:10 AM
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Default RE: engine noise

It was nice this weekend so I got a chance to take a better look for the source of the noise. I took the heat shield off of the pass side exhaust manifold. I thought the sound may have been originating near the back of the ex manifold. It was not.

It sounds like the noise may be coming the engine itself - back half - possibly in the valley under the intake. Pretty constant popping sound roughly one per second. It you goose the throttle the frequency picks up with the rpm but as the rpms come down it almost becomes a "rap-rap-rap" sound.

Also, when I was under the vehicle trying to find the source the pass side cat converter was shaking pretty crazily. The other one seemed to look normal. There is an exhaust leak because it smells like exhaust up front but nothing that can be easily seen.

Any suggestions.
 
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Old 04-10-2008, 08:48 PM
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Default RE: engine noise

Please reply to this chaps last post because this sounds similar to my dilema(regarding my 94 disco).
I suspect the converter thats what is sounded like anyway from underneath and only happens when hot.

I have no clue honestly

It will be taken to the muffler shop nextweek.

Thanks

~charlie
 
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Old 04-11-2008, 02:55 PM
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Default RE: engine noise

Someone locally has suggested a bent valve.

The popping sound is because the valve is not closing all the way on the piston stroke and the sound is travelling back through the system. The car seems to be running a little rich. Could be from incomplete combustion due to the valve not closing all the way.

Am going to do a compression test this weekend.
 
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Old 05-23-2008, 12:31 PM
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Default RE: engine noise

Finally figured it out. Ran a compression test and there was no compression in #8. Turns out that the head gasket was completely blown out on the side of the piston nearest the exhaust manifold. There was a chunk about an inch longthat was totally missing.
 
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Old 05-23-2008, 12:38 PM
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Default RE: engine noise

Good that you found the problem.
So make sure you shop around for the head gasket replacement and if you want to save lots of money don't use your local dealer.
 
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Old 05-23-2008, 07:38 PM
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Default RE: engine noise

I would not rule out your local dealer! They have the correct parts, and a 1 year warranty for the total repair!
 


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