Pulley rattle on cold starts
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From: Vancouver, BC
2002 C230 Coupe
Pulley rattle on cold starts
Hey guys,
So here's my dilemma: whenever I start the car after its been sitting overnight, or if the engine is otherwise old, I get this horrible rattling sound which seems to be coming from the pulleys. The sound only appears when the car is in gear (not in neutral or park) and disappears after the engine has only been running for about a minute or two.
After searching the forum I found a thread describing the same symptoms which said the issue was with the tensioner (idler) puller on the supercharger belt. I inspected it while the car was making the noise, and it did seem to be rattling more than would seem appropriate. So I bought a new one and stuck it on. No go. The noise is still there with the exact same symptoms.
I have an ASP crankshaft pulley on the car but otherwise the engine has not been modded. Any suggestions on what is causing the noise? It’s pretty loud and the car almost sounds like a diesel truck until the sound goes away. In short: it sucks.
Thanks for your help!
So here's my dilemma: whenever I start the car after its been sitting overnight, or if the engine is otherwise old, I get this horrible rattling sound which seems to be coming from the pulleys. The sound only appears when the car is in gear (not in neutral or park) and disappears after the engine has only been running for about a minute or two.
After searching the forum I found a thread describing the same symptoms which said the issue was with the tensioner (idler) puller on the supercharger belt. I inspected it while the car was making the noise, and it did seem to be rattling more than would seem appropriate. So I bought a new one and stuck it on. No go. The noise is still there with the exact same symptoms.
I have an ASP crankshaft pulley on the car but otherwise the engine has not been modded. Any suggestions on what is causing the noise? It’s pretty loud and the car almost sounds like a diesel truck until the sound goes away. In short: it sucks.
Thanks for your help!
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Joined: Oct 2006
Posts: 556
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From: Berlin
2018 C63s
I had the exact same thing happen to me like 2 weeks ago... I thought it was something really serious. It turned out to be the alternator pulley. Apparently one of the bearings on it went bad and it had to be replaced. After getting raped by the stealership, however, the problem went away. I paid about 530. Hope that helps. 
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From: Llandudno, Cape Town, South Africa
late 2009 CLK 350 Coupe Elegance, '65 Jaguar S Type wires
Hey guys,
So here's my dilemma: whenever I start the car after its been sitting overnight, or if the engine is otherwise old, I get this horrible rattling sound which seems to be coming from the pulleys. The sound only appears when the car is in gear (not in neutral or park) and disappears after the engine has only been running for about a minute or two.
After searching the forum I found a thread describing the same symptoms which said the issue was with the tensioner (idler) puller on the supercharger belt. I inspected it while the car was making the noise, and it did seem to be rattling more than would seem appropriate. So I bought a new one and stuck it on. No go. The noise is still there with the exact same symptoms.
I have an ASP crankshaft pulley on the car but otherwise the engine has not been modded. Any suggestions on what is causing the noise? It’s pretty loud and the car almost sounds like a diesel truck until the sound goes away. In short: it sucks.
Thanks for your help!
So here's my dilemma: whenever I start the car after its been sitting overnight, or if the engine is otherwise old, I get this horrible rattling sound which seems to be coming from the pulleys. The sound only appears when the car is in gear (not in neutral or park) and disappears after the engine has only been running for about a minute or two.
After searching the forum I found a thread describing the same symptoms which said the issue was with the tensioner (idler) puller on the supercharger belt. I inspected it while the car was making the noise, and it did seem to be rattling more than would seem appropriate. So I bought a new one and stuck it on. No go. The noise is still there with the exact same symptoms.
I have an ASP crankshaft pulley on the car but otherwise the engine has not been modded. Any suggestions on what is causing the noise? It’s pretty loud and the car almost sounds like a diesel truck until the sound goes away. In short: it sucks.
Thanks for your help!
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From: In Kush Land So cal
02 C320 Sedan
My car would do it when i first started it up. And it would go away after the car got warm. But i dunno what i did it no longer makes the sound. Im sure it will make a lot more sounds from the crash now =/
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From: Llandudno, Cape Town, South Africa
late 2009 CLK 350 Coupe Elegance, '65 Jaguar S Type wires
I"ve never heard of a 6 cyl doing it, but it's common on 4 cyl models. The 4 cyl models do it for a short period of time until full oil pressure is achieved. Has nothing to do with the engine warming up. Your problem must have been something else.
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From: Vancouver, BC
2002 C230 Coupe
I looked at the car again this morning, while it was rattling away and waking up the neighbors, and the rattle definitely seems to still be coming from the tensioner on the supercharger belt. I checked out the alternator pulley as mentioned in a previous post, but it seems to be running smooth.
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From: Llandudno, Cape Town, South Africa
late 2009 CLK 350 Coupe Elegance, '65 Jaguar S Type wires
Thanks Glyn, so you're saying I'd have to replace the actual tensioner unit then, not just the pulley?
I looked at the car again this morning, while it was rattling away and waking up the neighbors, and the rattle definitely seems to still be coming from the tensioner on the supercharger belt. I checked out the alternator pulley as mentioned in a previous post, but it seems to be running smooth.
I looked at the car again this morning, while it was rattling away and waking up the neighbors, and the rattle definitely seems to still be coming from the tensioner on the supercharger belt. I checked out the alternator pulley as mentioned in a previous post, but it seems to be running smooth.
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From: So. Oregon Coast
C230 Sport Coup + 2006 W164 ML350 + 99 Ford Escort RIP
Thanks Glyn, so you're saying I'd have to replace the actual tensioner unit then, not just the pulley?
I looked at the car again this morning, while it was rattling away and waking up the neighbors, and the rattle definitely seems to still be coming from the tensioner on the supercharger belt. I checked out the alternator pulley as mentioned in a previous post, but it seems to be running smooth.
I looked at the car again this morning, while it was rattling away and waking up the neighbors, and the rattle definitely seems to still be coming from the tensioner on the supercharger belt. I checked out the alternator pulley as mentioned in a previous post, but it seems to be running smooth.
Check the idler pulley as well.
It's not hard to replace the tensioner, it has like 3 or 4 bolts holding it on and can be R&R'd with standard tools.
Make sure you get the SC tensioner...most shops try to sell you the other one. Pn on the M111 for the SC tensioner is 1112001370 85 bucks at parts.com
I did this on oct 06 and it hasn't come back.
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From: Llandudno, Cape Town, South Africa
late 2009 CLK 350 Coupe Elegance, '65 Jaguar S Type wires
That worked for me....there was a thread by that guy in Portugal....forget his username where he had a video of that...yeh, the tensioner is the main culprit. I also replaced the pulley but I don't think it was necessary.
Check the idler pulley as well.
It's not hard to replace the tensioner, it has like 3 or 4 bolts holding it on and can be R&R'd with standard tools.
Make sure you get the SC tensioner...most shops try to sell you the other one. Pn on the M111 for the SC tensioner is 1112001370 85 bucks at parts.com
I did this on oct 06 and it hasn't come back.
Check the idler pulley as well.
It's not hard to replace the tensioner, it has like 3 or 4 bolts holding it on and can be R&R'd with standard tools.
Make sure you get the SC tensioner...most shops try to sell you the other one. Pn on the M111 for the SC tensioner is 1112001370 85 bucks at parts.com
I did this on oct 06 and it hasn't come back.
By all means change the belt tensioner if you wish
Last edited by Glyn M Ruck; Oct 24, 2008 at 04:14 PM.
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C230 Sport Coup + 2006 W164 ML350 + 99 Ford Escort RIP
I understood you were talking about timing chains, but IMHO and speaking from experience, you're barking up the wrong tree in this particular circumstance.
Last edited by C230 Sport Coup; Oct 24, 2008 at 04:37 PM.
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From: Llandudno, Cape Town, South Africa
late 2009 CLK 350 Coupe Elegance, '65 Jaguar S Type wires
This is a known issue on ASP pullied M111's, something I have personally experienced and resolved previously. I looked up the pn from my receipt.
I understood you were talking about timing chains, but IMHO and speaking from experience, you're barking up the wrong tree in this particular circumstance.
I understood you were talking about timing chains, but IMHO and speaking from experience, you're barking up the wrong tree in this particular circumstance.
But why confuse the issue by quoting
"Originally Posted by shizo
Thanks Glyn, so you're saying I'd have to replace the actual tensioner unit then, not just the pulley?" - evidence that shizo did not understand me.
And then continuing to talk about belt tensioners. All you do is confuse the poster. You have a habit of doing this which is a pity because you have some very good input.
If you disagree with me. Then say so - motivate why - then give your alternate opinion & motivate that. Then we all learn.
We both have different experiences with this engine. Either could be correct. Just be logical in your communication.
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2002 C230 Coupe
Thanks for the responses guys. I got out my stethoscope and played doctor on the car this evening, after I was sure the engine would be cold enough to rattle. No go on the chain housing, the sound definitely didn't appear to be coming from down there. I'm glad that was eliminated! Thanks for the suggestion though Glyn!
Hey C230, thanks for the input. Funny, I was pretty sure I had read somewhere in some old thread that you had experienced the same problem, but for the life of me I couldn't find it (I looked specifically for it because I know you're running an M111 with the ASP too). I think we're talking about the same post regarding the other guy that had the same problem, but his web links aren't working anymore, so I wasn't sure exactly what was going on. But that thread did lead me to replace the tensioner pulley. However, like you, when I took it off it seemed to be in pretty good shape, so I guess I probably didn't need to replace it. Another 100 bucks well spent!
Thanks for the part number for the tensioner unit. Looks like a bargain on parts.com, my dealership had a price well over 200 bucks, so I'm gonna order it. Hopefully that will solve it. I'll post an update after I put it on.
Thanks again!
Hey C230, thanks for the input. Funny, I was pretty sure I had read somewhere in some old thread that you had experienced the same problem, but for the life of me I couldn't find it (I looked specifically for it because I know you're running an M111 with the ASP too). I think we're talking about the same post regarding the other guy that had the same problem, but his web links aren't working anymore, so I wasn't sure exactly what was going on. But that thread did lead me to replace the tensioner pulley. However, like you, when I took it off it seemed to be in pretty good shape, so I guess I probably didn't need to replace it. Another 100 bucks well spent!
Thanks for the part number for the tensioner unit. Looks like a bargain on parts.com, my dealership had a price well over 200 bucks, so I'm gonna order it. Hopefully that will solve it. I'll post an update after I put it on.
Thanks again!
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Hey Shizo,
I had this same problem. The dealer replaced the tensioner, but they torqued the bolts too tight on the new tensioner. All was working well until a few mornings later, I gave it an extra rev and the entire tensioner snapped off.
The dealer spent a few thousand in parts/labour to fix that mess, luckily all under warranty. So be careful torquing the bolts correctly, I'm not sure where to find out what they should be torqued to, maybe check WIS.
They also replaced the alternator twice from what I can tell, and the serpentine belt, and maybe some other things too. I didn't look over the invoice in too much detail since I didn't have to pay, I was more concerned if it was fixed or not.
My symptoms were exactly the same as yours: hearing a squeal on cold starts for the first two minutes or so, that went away when in neutral.
I had this same problem. The dealer replaced the tensioner, but they torqued the bolts too tight on the new tensioner. All was working well until a few mornings later, I gave it an extra rev and the entire tensioner snapped off.
The dealer spent a few thousand in parts/labour to fix that mess, luckily all under warranty. So be careful torquing the bolts correctly, I'm not sure where to find out what they should be torqued to, maybe check WIS.
They also replaced the alternator twice from what I can tell, and the serpentine belt, and maybe some other things too. I didn't look over the invoice in too much detail since I didn't have to pay, I was more concerned if it was fixed or not.
My symptoms were exactly the same as yours: hearing a squeal on cold starts for the first two minutes or so, that went away when in neutral.
Last edited by c230yvr; Oct 25, 2008 at 01:57 AM.
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From: Llandudno, Cape Town, South Africa
late 2009 CLK 350 Coupe Elegance, '65 Jaguar S Type wires
Thanks for the responses guys. I got out my stethoscope and played doctor on the car this evening, after I was sure the engine would be cold enough to rattle. No go on the chain housing, the sound definitely didn't appear to be coming from down there. I'm glad that was eliminated! Thanks for the suggestion though Glyn!
Hey C230, thanks for the input. Funny, I was pretty sure I had read somewhere in some old thread that you had experienced the same problem, but for the life of me I couldn't find it (I looked specifically for it because I know you're running an M111 with the ASP too). I think we're talking about the same post regarding the other guy that had the same problem, but his web links aren't working anymore, so I wasn't sure exactly what was going on. But that thread did lead me to replace the tensioner pulley. However, like you, when I took it off it seemed to be in pretty good shape, so I guess I probably didn't need to replace it. Another 100 bucks well spent!
Thanks for the part number for the tensioner unit. Looks like a bargain on parts.com, my dealership had a price well over 200 bucks, so I'm gonna order it. Hopefully that will solve it. I'll post an update after I put it on.
Thanks again!
Hey C230, thanks for the input. Funny, I was pretty sure I had read somewhere in some old thread that you had experienced the same problem, but for the life of me I couldn't find it (I looked specifically for it because I know you're running an M111 with the ASP too). I think we're talking about the same post regarding the other guy that had the same problem, but his web links aren't working anymore, so I wasn't sure exactly what was going on. But that thread did lead me to replace the tensioner pulley. However, like you, when I took it off it seemed to be in pretty good shape, so I guess I probably didn't need to replace it. Another 100 bucks well spent!
Thanks for the part number for the tensioner unit. Looks like a bargain on parts.com, my dealership had a price well over 200 bucks, so I'm gonna order it. Hopefully that will solve it. I'll post an update after I put it on.
Thanks again!
Also file away in your memory the low oil pressure chain rattle. It's very common. - Good luck
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From: Vancouver, BC
2002 C230 Coupe
Wow. Its been a while, but I just realized I never followed up on this. So just a heads up for anyone experiencing the same problem: it was the tensioner as noted above in C230s post. The part number mentioned is accurate.
The fix is relatively easy: loosen the tension from the belt and remove. The pop the cap off the pulley itself and remove. Undo the three torx bolts to take the tensioner out. Some of the bolts are a little tricky to get to but otherwise not too bad. Installation is the reverse. Just don't over-tighten the new bolts as the torque is only approximately 25NM.
Its been a few months now since I did this job and there has been no noise at all.
The fix is relatively easy: loosen the tension from the belt and remove. The pop the cap off the pulley itself and remove. Undo the three torx bolts to take the tensioner out. Some of the bolts are a little tricky to get to but otherwise not too bad. Installation is the reverse. Just don't over-tighten the new bolts as the torque is only approximately 25NM.
Its been a few months now since I did this job and there has been no noise at all.
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C230 Sport Coup + 2006 W164 ML350 + 99 Ford Escort RIP
Wow. Its been a while, but I just realized I never followed up on this. So just a heads up for anyone experiencing the same problem: it was the tensioner as noted above in C230s post. The part number mentioned is accurate.
The fix is relatively easy: loosen the tension from the belt and remove. The pop the cap off the pulley itself and remove. Undo the three torx bolts to take the tensioner out. Some of the bolts are a little tricky to get to but otherwise not too bad. Installation is the reverse. Just don't over-tighten the new bolts as the torque is only approximately 25NM.
Its been a few months now since I did this job and there has been no noise at all.
The fix is relatively easy: loosen the tension from the belt and remove. The pop the cap off the pulley itself and remove. Undo the three torx bolts to take the tensioner out. Some of the bolts are a little tricky to get to but otherwise not too bad. Installation is the reverse. Just don't over-tighten the new bolts as the torque is only approximately 25NM.
Its been a few months now since I did this job and there has been no noise at all.
When I did this, I replaced the tensioner and the pulley.
It's been about 50K miles, and I'm starting to get the noise again, not bad yet...
So, did you just replace the tensioner and that solved the problem?
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From: So. Oregon Coast
C230 Sport Coup + 2006 W164 ML350 + 99 Ford Escort RIP
That might be so & time will tell.
But why confuse the issue by quoting
"Originally Posted by shizo
Thanks Glyn, so you're saying I'd have to replace the actual tensioner unit then, not just the pulley?" - evidence that shizo did not understand me.
And then continuing to talk about belt tensioners. All you do is confuse the poster. You have a habit of doing this which is a pity because you have some very good input.
If you disagree with me. Then say so - motivate why - then give your alternate opinion & motivate that. Then we all learn.
We both have different experiences with this engine. Either could be correct. Just be logical in your communication.
But why confuse the issue by quoting
"Originally Posted by shizo
Thanks Glyn, so you're saying I'd have to replace the actual tensioner unit then, not just the pulley?" - evidence that shizo did not understand me.
And then continuing to talk about belt tensioners. All you do is confuse the poster. You have a habit of doing this which is a pity because you have some very good input.
If you disagree with me. Then say so - motivate why - then give your alternate opinion & motivate that. Then we all learn.
We both have different experiences with this engine. Either could be correct. Just be logical in your communication.
"Glyn, you ignorant ****."
Gotcha!!
Last edited by C230 Sport Coup; Mar 27, 2009 at 03:30 AM.
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From: Llandudno, Cape Town, South Africa
late 2009 CLK 350 Coupe Elegance, '65 Jaguar S Type wires
I was waiting for a reply from the now catty old tart . I don't care who was right or wrong - the problem got solved & that's gr8. I stand by my comment that your communication could have been better so as not to obfuscate the issue.
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I replaced the pulley first, and that did nothing. The noise was still there after as loud as ever. I replaced the tensioner next and it was gone right away. So ya, just replace the tensioner an you should be fine! You say yours lasted about 50k? Good! Hopefully that means I have a couple of years before that needs to be done again...
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C230 Sport Coup + 2006 W164 ML350 + 99 Ford Escort RIP
I replaced the pulley first, and that did nothing. The noise was still there after as loud as ever. I replaced the tensioner next and it was gone right away. So ya, just replace the tensioner an you should be fine! You say yours lasted about 50k? Good! Hopefully that means I have a couple of years before that needs to be done again...
Glyn, Obsfucation is your specialty.
I especially love your many replies where you state, 'gee I dunno what it could be'
instead of just not replying.
You've managed to accumulate more posts in 8 months on this forum, than I have in 7+ years.Then again, there's times when you post reams of great and occasionally accurate info, so it all evens out.
I held my tongue back in Oct. but I couldn't help myself when the response came back, that yes, I was right on the money and in my 1st post in the thread. As Kevin Spacey once said, "I rule".
Last edited by C230 Sport Coup; Mar 27, 2009 at 05:14 PM.
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From: So. Oregon Coast
C230 Sport Coup + 2006 W164 ML350 + 99 Ford Escort RIP
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From: Llandudno, Cape Town, South Africa
late 2009 CLK 350 Coupe Elegance, '65 Jaguar S Type wires
Actually it's still OK, only does it a little when it's cold, but it will likely gradually get worse. I'm holding off on buying a new tensioner for the time being after spending 500 on misc parts around Christmas time, including the new grill.
Glyn, Obsfucation is your specialty.
I especially love your many replies where you state, 'gee I dunno what it could be' instead of just not replying. You've managed to accumulate more posts in 8 months on this forum, than I have in 7+ years.
Then again, there's times when you post reams of great and occasionally accurate info, so it all evens out.
I held my tongue back in Oct. but I couldn't help myself when the response came back, that yes, I was right on the money and in my 1st post in the thread. As Kevin Spacey once said, "I rule".
Glyn, Obsfucation is your specialty.
I especially love your many replies where you state, 'gee I dunno what it could be'
instead of just not replying. You've managed to accumulate more posts in 8 months on this forum, than I have in 7+ years.Then again, there's times when you post reams of great and occasionally accurate info, so it all evens out.
I held my tongue back in Oct. but I couldn't help myself when the response came back, that yes, I was right on the money and in my 1st post in the thread. As Kevin Spacey once said, "I rule".
I'm happy I help more than I hinder.
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From: Bay Area, CA
W205 C63 Cabriolet
Sorry to bring back an old thread but I have this same problem and I can't find instructions anywhere on how to take out the tensioner? I'm trying to replace the pulley and as far as I've learned in order to do this I need to take off the tensioner as well? And in order to take off the tensioner I apparently need to take off the supercharger which I can't find instructions for either??? :/
