Another Engine Noise Thread
06-24-2020, 06:49 PM
#1
Rennlist Member
Thread Starter
Another Engine Noise Thread
2003 C4 Cab
Metallic ticking (but a little more like hollow clanking) on the right side, sootier tailpipe on the left. OMG my engine's toast, call Jake. I couldn't really pinpoint the noise with a standard stethoscope (in retrospect I think despite having the stethoscope in my ears, my hearing aids amplified the sound all around me. duh).
I was going to replace the spark plugs and poke a camera in to get a look. Two things happened. One, when taking off the right side muffler, I found that two of the 3 studs holding it to the engine bracket were broken. allowing for a bit of movement. You know, like a metallic clanking. BINGO. Two, my camera was too big to fit.
Excited that the muffler was the problem I finished the plugs and coils and got it all back together. No change. No Bingo.
Then for Father's Day I got an electronic stethoscope and a digital manometer. Whoo hoo! Made a test cap and measured 4.53 inH20 (how do you write that?) so that was good. Busted out the stethoscope and the noise is absolutely not coming from the engine itself - I notice it the most along the seam closest to the wheel well on the right muffler...but that's about it. It was raining last night so I quit.
After work today my son and I put it up on ramps to be more thorough - definitely coming from where I thought, it is loudest on the right muffler, right behind the wheel. Then I noticed a crack about three inches long in the seam - and that is right where it's loudest. Really? All this stress and anxiety and it's going to be a little exhaust leak!? It really sounds like a metallic tapping.
On a related note - I don't think the PSE is working. Well, I mean pushing the button makes no difference so I'm sure it's stuck on or off. I assume it's stuck in loud mode because it sounds great and I'm okay with that, but I'd like to know if it's working right or not. When I had the mufflers off to do the plugs and coils, I made sure the linkage for the valves moved freely because I thought that might have been the source of the noise.
I just realized I should have pulled the vacuum line while it was running. I'll try that later. When I disconnect the brown/orange connector, there are two connections - I haven't found a diagram so I'm not sure if I should check for voltage across them, or from either or both to ground. I presume button on and off should result in different readings to one or both of those wires.
Any tips on testing that circuit and changeover valve? Oh - if the relay was no good (or missing, I haven't checked) would the light on the button still light up, or would that only happen if the relay closed? I'm wondering about that because I'm not sure the car gets quiet when its supposed to either, which could mean somebody just pulled the relay and that's why it stays loud - but would that light come on?
Metallic ticking (but a little more like hollow clanking) on the right side, sootier tailpipe on the left. OMG my engine's toast, call Jake. I couldn't really pinpoint the noise with a standard stethoscope (in retrospect I think despite having the stethoscope in my ears, my hearing aids amplified the sound all around me. duh).
I was going to replace the spark plugs and poke a camera in to get a look. Two things happened. One, when taking off the right side muffler, I found that two of the 3 studs holding it to the engine bracket were broken. allowing for a bit of movement. You know, like a metallic clanking. BINGO. Two, my camera was too big to fit.
Excited that the muffler was the problem I finished the plugs and coils and got it all back together. No change. No Bingo.
Then for Father's Day I got an electronic stethoscope and a digital manometer. Whoo hoo! Made a test cap and measured 4.53 inH20 (how do you write that?) so that was good. Busted out the stethoscope and the noise is absolutely not coming from the engine itself - I notice it the most along the seam closest to the wheel well on the right muffler...but that's about it. It was raining last night so I quit.
After work today my son and I put it up on ramps to be more thorough - definitely coming from where I thought, it is loudest on the right muffler, right behind the wheel. Then I noticed a crack about three inches long in the seam - and that is right where it's loudest. Really? All this stress and anxiety and it's going to be a little exhaust leak!? It really sounds like a metallic tapping.
On a related note - I don't think the PSE is working. Well, I mean pushing the button makes no difference so I'm sure it's stuck on or off. I assume it's stuck in loud mode because it sounds great and I'm okay with that, but I'd like to know if it's working right or not. When I had the mufflers off to do the plugs and coils, I made sure the linkage for the valves moved freely because I thought that might have been the source of the noise.
I just realized I should have pulled the vacuum line while it was running. I'll try that later. When I disconnect the brown/orange connector, there are two connections - I haven't found a diagram so I'm not sure if I should check for voltage across them, or from either or both to ground. I presume button on and off should result in different readings to one or both of those wires.
Any tips on testing that circuit and changeover valve? Oh - if the relay was no good (or missing, I haven't checked) would the light on the button still light up, or would that only happen if the relay closed? I'm wondering about that because I'm not sure the car gets quiet when its supposed to either, which could mean somebody just pulled the relay and that's why it stays loud - but would that light come on?
