Glow plug relay
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Joined: Feb 2018
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CL500, W212 e350 mega-spec
Glow plug relay
Hi everybody.
The car is a 2004 E320 CDI. It has the warning light on the dash for glow plugs. I plugged it into a simple code reader and got P0683. I cleared it and it came back straight away. I cleared it again and it came back again.
So I'm going to change the glow plug relay.
I think with it being a 2004 it is going to be the square type bolted onto the bottom of the intake manifold though I am yet to verify this. If anybody knows that'd be great.
This one is cheap enough for me but it says it's for a BMW. On the top of the unit you can see it says 12v 6-cyl and it seems to have the same plugs as the Mercedes one I've been looking at. It's less than half the price of the Mercedes one. What do people think: https://www.ebay.co.uk/itm/385255147143
The car is a 2004 E320 CDI. It has the warning light on the dash for glow plugs. I plugged it into a simple code reader and got P0683. I cleared it and it came back straight away. I cleared it again and it came back again.
So I'm going to change the glow plug relay.
I think with it being a 2004 it is going to be the square type bolted onto the bottom of the intake manifold though I am yet to verify this. If anybody knows that'd be great.
This one is cheap enough for me but it says it's for a BMW. On the top of the unit you can see it says 12v 6-cyl and it seems to have the same plugs as the Mercedes one I've been looking at. It's less than half the price of the Mercedes one. What do people think: https://www.ebay.co.uk/itm/385255147143
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Joined: Dec 2021
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E350 4matic Wagon
Hi everybody.
The car is a 2004 E320 CDI. It has the warning light on the dash for glow plugs. I plugged it into a simple code reader and got P0683. I cleared it and it came back straight away. I cleared it again and it came back again.
So I'm going to change the glow plug relay.
I think with it being a 2004 it is going to be the square type bolted onto the bottom of the intake manifold though I am yet to verify this. If anybody knows that'd be great.
This one is cheap enough for me but it says it's for a BMW. On the top of the unit you can see it says 12v 6-cyl and it seems to have the same plugs as the Mercedes one I've been looking at. It's less than half the price of the Mercedes one. What do people think: https://www.ebay.co.uk/itm/385255147143
The car is a 2004 E320 CDI. It has the warning light on the dash for glow plugs. I plugged it into a simple code reader and got P0683. I cleared it and it came back straight away. I cleared it again and it came back again.
So I'm going to change the glow plug relay.
I think with it being a 2004 it is going to be the square type bolted onto the bottom of the intake manifold though I am yet to verify this. If anybody knows that'd be great.
This one is cheap enough for me but it says it's for a BMW. On the top of the unit you can see it says 12v 6-cyl and it seems to have the same plugs as the Mercedes one I've been looking at. It's less than half the price of the Mercedes one. What do people think: https://www.ebay.co.uk/itm/385255147143
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Joined: Dec 2021
Posts: 192
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E350 4matic Wagon
hey snarky man, because it was likely to be in the same general area. Here, I did your research for you. Sorry you didn’t find my earlier comment useful.
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CL500, W212 e350 mega-spec
They're very different cars.
I saw quite a few individual write-ups on changing the relay on the 2004 model and I'm pretty sure it is bolted to the bottom of the intake manifold. That's the first place I'm going to look when I tackle this job on Saturday. I think I'll just have a look to confirm what type it is before buying a replacement. There is also the possibility of lose or corroded terminals so worth having a little look before ordering anything.
I'm assuming the reason it is bolted to the underside of the inlet manifold is that the back of the relay is a heatsink. It bolts to the aluminium intake manifold to increase heat transfer out of the relay even further.... this is assuming it is where I think it is.
I saw quite a few individual write-ups on changing the relay on the 2004 model and I'm pretty sure it is bolted to the bottom of the intake manifold. That's the first place I'm going to look when I tackle this job on Saturday. I think I'll just have a look to confirm what type it is before buying a replacement. There is also the possibility of lose or corroded terminals so worth having a little look before ordering anything.
I'm assuming the reason it is bolted to the underside of the inlet manifold is that the back of the relay is a heatsink. It bolts to the aluminium intake manifold to increase heat transfer out of the relay even further.... this is assuming it is where I think it is.
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1991 300D, 2006 E320 CDI, 2014 E250 Bluetec
I have an 06 E320 CDI and that's where it's located....under the intake, toward the back IIRC. At least for me, it was difficult to access....I ended up having my indie replace it. Most folks access it from below....I read of at least one guy accessing from above....must have had rubber arms or something.
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CL500, W212 e350 mega-spec
I used to be a mechanic so if it can be done from above that's what I'd rather. If you go from underneath you've got to get the car up in the air and take off undertrays and I would just be doing this at home so no access to lift. I'd rather just deal with a couple of awkward screws and take it out from above.
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CL500, W212 e350 mega-spec
Glad I held off on buying anything. I looked under the intake manifold but couldn't see it. On my 2004 it is under the coolant tank and it is the older type. For now I've removed it and cleaned all the terminals as without knowing which one it was I didn't buy anything. I'm wondering if simply removing it and cleaning will fix it but that doesn't always work.
I found another problem while I was under there so now waiting for silicone to cure before starting the engine. Leaking injector. Had to tackle that straight away as I thought the car was a bit stinky and now I know why. So hopefully that's sorted as well.
I found another problem while I was under there so now waiting for silicone to cure before starting the engine. Leaking injector. Had to tackle that straight away as I thought the car was a bit stinky and now I know why. So hopefully that's sorted as well.
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2006 E280
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CL500, W212 e350 mega-spec
Well it's a separate topic. But there was a YouTube video showing a guy fixing it with silicone.
I tried it and it lasted for a minute before blowing out.
When I took the injector out again (much easier the second time, only a few minutes) I found the original copper washer which I couldn't remove from the tube on Saturday I was able to nudge loose with a screwdriver and lift out with a hooked piece of wire. The real problem was the original washer had been crushed and gone oblong and had soot marks on it showing where it was blowing.
I put in a new washer and for extra piece of mind I added a tiny smear of rapid setting chemical metal. Now it does not leak! - so silicone no good... chemical metal much better. But ultimately they would have sealed from the factory with nothing on them so it will be the condition of the mating surfaces which matters most of all. Then probably best to fit the correct kind of copper washer... I used a generic one but it is holding for now so fingers crossed.
I tried it and it lasted for a minute before blowing out.
When I took the injector out again (much easier the second time, only a few minutes) I found the original copper washer which I couldn't remove from the tube on Saturday I was able to nudge loose with a screwdriver and lift out with a hooked piece of wire. The real problem was the original washer had been crushed and gone oblong and had soot marks on it showing where it was blowing.
I put in a new washer and for extra piece of mind I added a tiny smear of rapid setting chemical metal. Now it does not leak! - so silicone no good... chemical metal much better. But ultimately they would have sealed from the factory with nothing on them so it will be the condition of the mating surfaces which matters most of all. Then probably best to fit the correct kind of copper washer... I used a generic one but it is holding for now so fingers crossed.
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2006 E280
I was afraid you were talking about that specific leak. You better get the original copper washer ASAP, and a tool for reaming the mating surface of the head. Sooner you do it, the better. There is a chance you ruin the head, even the injector, too.
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CL500, W212 e350 mega-spec
I'm not going to panic. I found a big problem which I've fixed so I don't expect there to be problems from now on.
