Exhaust leak sound only under a load
#1
Exhaust leak sound only under a load
Hey guys I'm hoping one of you might know.
I have a 2000 Ranger XLT with the 3.0. It has what sounds like an exhaust leak, but only under a load. I can't hear it with the truck parked and hood up. Revving the engine without a load doesn't create the sound either. The EGR tube has no holes that I can find and the sound is coming from the drivers side. Could possibly be where the tube attaches to the manifold, but it doesn't seem to be loose. Could a bad EGR make a sound like an exhaust leak? I can't figure it out, there isn't any soot anywhere around the manifold like you would normally find when there's a leak. Check engine light isn't on and it's not throwing any codes. Any help will be greatly appreciated.
I have a 2000 Ranger XLT with the 3.0. It has what sounds like an exhaust leak, but only under a load. I can't hear it with the truck parked and hood up. Revving the engine without a load doesn't create the sound either. The EGR tube has no holes that I can find and the sound is coming from the drivers side. Could possibly be where the tube attaches to the manifold, but it doesn't seem to be loose. Could a bad EGR make a sound like an exhaust leak? I can't figure it out, there isn't any soot anywhere around the manifold like you would normally find when there's a leak. Check engine light isn't on and it's not throwing any codes. Any help will be greatly appreciated.
#2
To test if its the EGR valve(which only opens under load) get the correct size vacuum line and remove the EGR valve's vacuum line, put your vacuum line on EGR Valve.
Start engine and let it idle.
Suck on the added vacuum line to open the EGR valve, just a bit or engine will die, listen for exhaust leak.
No, you won't be sucking in exhaust, if you do then EGR valve needs to be replaced, lol.
Another method to check the manifolds and pipes is to start engine and have someone hold a shop rag over the tail pipe, blocking flow, this will increase the back pressure and make a leak more noticeable.
What can happen over time is the the cat converter can start to collapse inside, so get blocked up, under load back pressure builds up so that is when you notice a leak, usually you would also have sluggish performance at higher RPMs as well if exhaust flow is limited.
Start engine and let it idle.
Suck on the added vacuum line to open the EGR valve, just a bit or engine will die, listen for exhaust leak.
No, you won't be sucking in exhaust, if you do then EGR valve needs to be replaced, lol.
Another method to check the manifolds and pipes is to start engine and have someone hold a shop rag over the tail pipe, blocking flow, this will increase the back pressure and make a leak more noticeable.
What can happen over time is the the cat converter can start to collapse inside, so get blocked up, under load back pressure builds up so that is when you notice a leak, usually you would also have sluggish performance at higher RPMs as well if exhaust flow is limited.
#3
#5
What "sounds like" an exhaust leak may be the key here.
After looking at all exhaust leak points, logic would have you eliminate that as the possible source of "the noise" you hear.
So what else makes a noise under load............pre-detonation, pinging/knocking will only start under load.
Could just be restricted EGR tube/valve, flow is a little less than it should be so you get a ping/knock which could sound like an exhaust leak.
If you want to see if that's what the noise is run higher octane fuel next tank, if noise is less or gone then that's what it is.
Unfortunately a connecting rod bearing starting to fail can also sound like an exhaust leak, or visa versa, but this type of failure will get much worse fairly fast, so if it's been a few weeks that ain't it
After looking at all exhaust leak points, logic would have you eliminate that as the possible source of "the noise" you hear.
So what else makes a noise under load............pre-detonation, pinging/knocking will only start under load.
Could just be restricted EGR tube/valve, flow is a little less than it should be so you get a ping/knock which could sound like an exhaust leak.
If you want to see if that's what the noise is run higher octane fuel next tank, if noise is less or gone then that's what it is.
Unfortunately a connecting rod bearing starting to fail can also sound like an exhaust leak, or visa versa, but this type of failure will get much worse fairly fast, so if it's been a few weeks that ain't it
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#12
well guys I checked the EGR, and it doesn't look restricted. could be a bad EGR but I checked it by hooking up a vacuum line and applying a little vacuum. to much and the engine wants to die. There's no plastic elbow on my EGR. Have run Premium gas with a bottle of Royal Purple max clean, maybe it's wishful thinking but noise seems to be a little less after using 1/2 tank. I'm at a loss I've checked the fittings on the EGR tube every thing tight at the EGR but can't move the fitting at the exhaust manifold sprayed it with PB and will check tomorrow. Help any other ideas?
#13
Fixed part of the problem. A few weeks ago I replaced the cam synchronizer. I used the easy method, well I was off a little, and had it advanced which caused a detonation ping that added to the exhaust leak sound. After I set it correctly a lot of the sound was gone, but there is still an exhaust leak sound which I haven't been able to find. I believe it's either the EGR tube fitting at the exhaust manifold or connection between the manifold and exhaust pipe. I only hear it under load and have to turn off the radio to hear it. At this point it's mostly annoying and will continue to search for it. Problem with being a perfectionist.
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