E55 AMG Coolant disappearing without any leaks whatsoever.
I filled up the car with coolant and ever since the coolant is just disappearing without any signs of leak anywhere.
I took it to multiple garages and have it checked out by pressure test etc.
I asked the previous owner about this and he told me I should’ve flushed out the old coolant fully and then refilled. I think he is lying and the car already had this issue because in the listing he stated that the car needs service because it was sitting for a while.
The car has headers, injectors and snow performance methanol kit. The previous owner told me it makes 650hp although I never use the methanol system and never used it. The methanol wires are disconnected.
It’s my first car ever and I’m super sad that it has this issue, please let know what could be the issue because a few mechanics told me it’s a head gasket issue.
thank you in advance.




1 - Coolant tank cap. When old, it cannot hold pressure, and the coolant leak around the cap --> Dirty tank with dry coolant around the cap
2 - Coolant leak through the head gasket (blown head gasket) --> Need to pressurize the cooling system manually and check if it holds pressure, if it does not there is a leak somewhere
3 - Some W211 class cars (do not have the timeframe data) had a radiator issue where coolant mixed with the transmission oil (to make mayo), and by the time you notice it the transmission is history.
4 - Leak around connection points : hoses, thermostat, radiator, etc.
Aside, in my very personal opinion, this is not the first car for anyone, not even new.
1 - Coolant tank cap. When old, it cannot hold pressure, and the coolant leak around the cap --> Dirty tank with dry coolant around the cap
2 - Coolant leak through the head gasket (blown head gasket) --> Need to pressurize the cooling system manually and check if it holds pressure, if it does not there is a leak somewhere
3 - Some W211 class cars (do not have the timeframe data) had a radiator issue where coolant mixed with the transmission oil (to make mayo), and by the time you notice it the transmission is history.
4 - Leak around connection points : hoses, thermostat, radiator, etc.
Aside, in my very personal opinion, this is not the first car for anyone, not even new.
I did change the coolant cap with a new one and there was no change but I believe the mechanics just wanna pull the engine out a make a quick buck. I honestly don’t know what to do because I drive the car for an hour or 2 and have to fill it up again. Whole gallon.
A week ago a mechanic was checking the car and the exhaust was spitting coolant which it has never done before. I also notice black dots on the back of the car the car is white and it’s very apparent but I don’t see any black smoke.
I love the amg cars and it was my dream to own one but this was an unlucky purchase.
There are also kits to see if there is combustion gases on the coolant.
Last edited by Heguli; May 4, 2023 at 01:26 PM.




There are also kits to see if there is combustion gases on the coolant.
If you follow the boroscope route, you can combine it with pressurizing the coolant reservoir. With the boroscope you will see the coolant seeping into the cylinder nearest to the blown head gasket
Trending Topics
There are also kits to see if there is combustion gases on the coolant.
I’m very skeptical of getting the engine removed and get the head gasket changed if it’s certainly the case because the mechanics told me that once the engine is removed and disassembled it’s not the same anymore and it’s gonna create new problems or worse. They suggested me to buy a new car rather than get the gasket changed.
The Best of Mercedes & AMG




For a video series on rebuilding an E55 engine
If you buy another MB, get a normal engine with reasonable mileage, never ever modified/tuned unless you have deep pockets or you can do work yourself. There is no point in having a sports car if it spends most of the time being fixed regardless of brand or look.
If you have a desire to enjoy something special/dream, rent it or lease it and once you are convinced you really want to repeat the experience, you buy it.
Last edited by JCM_MB; May 4, 2023 at 02:03 PM.
https://www.youtube.com/watch?v=kY9ZpVpLl9Y
For a video series on rebuilding an E55 engine
https://www.youtube.com/watch?v=HapB...A39kyQ&index=9
If you buy another MB, get a normal engine with reasonable mileage, never ever modified/tuned unless you have deep pockets or you can do work yourself. There is no point in having a sports car if it spends most of the time being fixed regardless of brand or look.
If you have a desire to enjoy something special/dream, rent it or lease it and once you are convinced you really want to repeat the experience, you buy it.
I originally intended to buy a fully stock e55 or a cls55 but they were out of my budget for now and I wanted a car asap because I just got my driving license a month ago and got the e55 exactly after a month. I ran out of patience and it’s partially my fault to not stick with my original intentions. Lesson learned the hard way for real.
The best thing you can do for the car and for yourself is invest in a pile of tools, get the WIS/EPC from ebay, and learn how to do this yourself. You'll appreciate the whole package a whole lot more after you've invested the time into repairing something, and it'll be yours. You'll also be far more attached to it and thusly far less likely to have your next post be about how you nearly went all Paul Walker on a phone pole.
Just for reference, the dealer wanted well over $5K to replace the head gaskets on my Duramax several years ago. That was when I learned how to be a diesel mechanic, and I did a job far better and beyond (water pump, a few other goodies) than the dealer would have for about $2.5K. That leaves room for a lot of tools...
Last edited by rapidoxidation; May 4, 2023 at 10:49 PM.




At 65,000 miles you also need replacement of AMG fuel pumps and filter and relay; $1000 USD for parts, no labor. Also time for serpentine and supercharger belts plus tensioners and idler pulleys; figure low range of $300 USD (rebuild supercharger idler pulley yourself) to high range of $800 USD (install new supercharger idler pulley) for those parts.
I find it very, very difficult to believe the former owner was not aware of the coolant issue. If he was, I wish that Karma bites him in the *** three times over.
Are you in Europe or Canada? You refer to kilometers rather than miles. Might make a difference in support.
Best wishes to you.
The best thing you can do for the car and for yourself is invest in a pile of tools, get the WIS/EPC from ebay, and learn how to do this yourself. You'll appreciate the whole package a whole lot more after you've invested the time into repairing something, and it'll be yours. You'll also be far more attached to it and thusly far less likely to have your next post be about how you nearly went all Paul Walker on a phone pole.
Just for reference, the dealer wanted well over $5K to replace the head gaskets on my Duramax several years ago. That was when I learned how to be a diesel mechanic, and I did a job far better and beyond (water pump, a few other goodies) than the dealer would have for about $2.5K. That leaves room for a lot of tools...
I wish I could invest in tools and work on the car myself but I live in an apartment and have no place to open up the car and work on it. This is the one of the reasons why I was hoping it wasn’t a big issue which is going to cost thousands of dollars.
thank you so much for the suggestions.
At 65,000 miles you also need replacement of AMG fuel pumps and filter and relay; $1000 USD for parts, no labor. Also time for serpentine and supercharger belts plus tensioners and idler pulleys; figure low range of $300 USD (rebuild supercharger idler pulley yourself) to high range of $800 USD (install new supercharger idler pulley) for those parts.
I find it very, very difficult to believe the former owner was not aware of the coolant issue. If he was, I wish that Karma bites him in the *** three times over.
Are you in Europe or Canada? You refer to kilometers rather than miles. Might make a difference in support.
Best wishes to you.
That sucks big time I would’ve lost all hope of anything like that ever happened to me.
the previous owner definitely lied to me because when I first checked out the car check engine light lit up and he said it’s not a big issue but when I got the car diagnosed it says injector at cylinder 3 is bad.
I live in Turkey we use kilometers




brother I wish I could do that 😂 I’m so desperate to get this car fixed i love the car but it’s an unfortunate situation.
thank you so much for the offer boss
I got the engine removed and the issue was within the right head of the engine. I got a new head and it’s getting it’s valve seals done, bore, etc…
The video shows that the head was leaking pretty bad and that explains why there was almost no coolant after driving the car for about 30-40 minutes.



