Is there a way to get the fans to turn on sooner? I have been monitoring my coolant temps and after the engine fully warms up and i let it idle, the temp reading from the scan data will read 222f then creeps to 224, 226 then 230F and then the fans come on full blast and it cools back down to 208F. Not going base off of the dash temp reading because in my experience they are always highly inaccurate. Now I would like my engine to never get over 220F. On my previous silverado my predator programmer let me set my fan duty cycle to whatever i wanted according to the coolant temp. Does anyone know of anything similar for our w212 platform? In my opinion this is unacceptable for a turbo high output engine that is going to get pushed. Especially with the cylinder walls on this engine and the exhaust valve issues. Its no wonder we are having issues. I want to purchase an edge cts engine monitor and see if it will work with our ecu to display engine data and possibly hook up an egt pyrometer to monitor exhaust gat temps. How is it that people are tuning their cars and running them hard with out knowing accurate coolant temps, egts, boost pressure, iat, and afr? sounds like more engines could be saved if we paid more attention to these readings. I come from owning and building 2jzgte supras, duramax diesel trucks, and we always pay attention to these things. Anyways, I think starting with getting coolant temps to 195F for some head room ( to run hard and not melt things down) and keep engine away from 220+ idling temps before fans go full on will make for a big improvement in engine life. Btw when i purchased my e63 I noticed i had a small pinhole leak in an intercooler hose and it would slowly lose coolant. I have since replaced the hose and wired the intercooler pump to be on all the time. a must do on these cars. I feel like these m157 engine can me made way more reliable buy getting them to run a tad cooler, runing the intercooler pumps all the time, running good fuel, and monitoring engine vitals ( afr, egt, iat, boost) . what are your thoughts? and if anyone is already doing this please inform us on how and what products you are using.

 

Does IAT mod help?

 

https://mbworld.org/forums/w212-amg/...-rewiring.html

 

Yes it definitely helps and is a 100% must do in my opinion. It comes on way too late in stock configuration. Not sure why it was programmed that way. It is one of the keys to the puzzle of keeping these things alive and failure free.

 

My iat stay in the 80-90f range when around town and even some spirited driving. I’ll keep an eye on it as the weather gets warmer

 

I have three tunes - all have the fan coming on sooner (coded in)

 

It's really easy to adjust the fan regulation with Star/xentry up to 10° cooler on my E 55. Haven't tried it on the 157 engine yet.

 

Interesting. I’ll have to look into that. If anyone knows if it is possible with the e63 please let us know

 

Lets look at the 600lbs gorilla in the corner....you need a thermostat. Possibly a water pump as well. Something is PHYSICALLY not correct with your car.

 

Agreed. There would be no advantage running the fan at a lower temp if your thermostat is not opening. On my 113 K engine I have split cooling and IC pump on all the time.

 

True, strange decision from MB they must have their reasons I guess.

 

if my tstat was not opening it would be overheating instantly and running hot all the time. Which it doesn’t. T stats only help the engine warm up faster and don’t help with much passed their opening point. Once they are fully open they are open. Job is done. The coolant fans keep the temp from running away. T stats only there to regulate bottom
end of temp range. That’s why when they stick open your car runs too cool and sets p128. If they fail to open they over heat instantly since coolant can’t get to the radiator and hot coolant is just being circulated back into itself. Have you read your coolant temp with a real scanner (don’t use amg screen) to see what your temps reach? It may be very similar to mine. Warm it up and let it idle and see when ur fans turn on and temp start to retreat. The fans coming on set your top end max coolant temp so to speak. My other cars get to 212f ish and then fans really come on hard and cools back to 199f.

Water pump possible I guess if the impeller has separated from the shaft and is spinning less rpm and not flowing as much as it should. Has anyone had that occur on a m157? I have heard the pulleys like to “walk” off of the shaft belt side but what about the impeller side?

 

Low flowing pump still wouldn’t explain fans coming on so late. If it was a low flow conditions fans would come on full blast and still would have trouble cooling. I’m telling you this is normal and Mercedes has just set the fan temp too high. Why I have no idea. Fans come on mildly in the 200f range but really don’t go full blast till over 220. Even close to 230f it’s not good for the engines. Too close to the limit

 

Seen a few examples of water pumps (and pipes) littered with crap, plastic, RTV and other things limiting flow. On the M157, including mine. Few others

 

can you take us where fan regulation is adjusted ??

 

Motor electronics, correction programming electric suction fan.


It looks like my normal bidirectional scan tool will do it too.

 

There's a lot of Star DIY's in a sticky at the 211 AMG forum.

 

One thing to note when adjusting your fan temp is you end up with roaring high speed fan at idle when the car is warmed up. I adjusted mine to the maximum 10° so maybe turning it down a bit would help. it's my understanding that the primary design of this adjustment is to improve air conditioning performance in very hot climates.

 

Thank you for the info! Going to give it a try. Just wanting to get the fans on a bit earlier, a few degrees would be perfect.

 

it's 2° here in Wisconsin and my car is put away for the winter or I would try it for you. when you access the adjustment, add positive values to lower the cut in temperature. Negative values will make it turn on hotter.

 

agreed. The fan practically screams it's so loud. I think they called it "gulf mode" to accommodate higher temp climates like you said

 

it's impressive for sure and makes you wonder how many amps the fan wiring can sustain. I think there's another version of this mod accessed through the climate control special functions. It also changes the bias of the cabin airflow so more comes out the dash vents.

 

well, you would hope these would be over engineered a bit however, based on patterns seen in Mercedes engineering, I have less faith in that belief.

 

It's amazing how a basic function has been made sophisticated to yield substandard results.

We would expect MB cooling to be better than perfect instead we got a run away steam boiler from factory.

You can read the WIS doc to understand how everything is state of the art then you're left wondering why the reality is poor temp control.

Couple experimental steps can make engine temperature normal.



We're gonna take a part this hot pickle while sight seeing...


flipping cold
​​​

tapping Himalayan powers

The first thing to realize is the factory bias is extremely hot ie. "nothing wrong". Dealers can not make these cars anything but extremely hot.
To get any different result you'll need to go non-stock experimental.

> Lansdcape of heat Mgt:
ECU firmware is in charge of delivering factory experience using historical map translations.
The actial heat solution is not a real-time response.

> Heat sources are:
TT + Cylinders.

> Controls are :

• Managed Tstat
• Fan Rpm
• pump pressure

> Xfer circuits are :

• engine oil
• engine coolant
• TT coolant

> ALL RIGHT THEN ... ?
-- What's wrong is heat removal is made inefficient.
-- The engine packs extreme heat with very little ability to remove heat.

-- A new car is made to behaves like a clunker with dirty radiator.

-- Every engine plastic pipes, sensor snd seals gets fried into opportunities.

-- Driving a short 5Mi in winter reveal the inability to cool. FAN comes ON and keeps running.


> PRACTICALLY:
-- MOD-4 effective piston cooling
-- Smoothed ECU maps (10+kMi)
-- Tweak the TSTAT map!?!


> OUTCOME:
-- No fan running non-stop
-- Front struts are not kept bouncy hot.
-- ENGINE HEAT LEVEL IS UNBELIEVABLY NORMAL!


> Point being:
Busy fan does not remove heat
Pistons need not store heat
Tstat is made lazy by ECU Ctl
Heat does NOT simply get controlled as soon as pistons are sprayed, only gradually.

 

The temps seem normal for stock to me. Mine would get up there too, until I got HP Tuners, now I have full control of the fan. I would be ~185 on the freeway, a bit more is summer heat. At idle it would generally stay ~195 because the fan would start at 195 (0% speed), and by 198 it's 30% (see pix), and it doesn't take but 5-10% to maintain temp at idle, assuming the A/C is off. As for fan noise, there is none, generally. With the eng off in my silent driveway, door open, I cannot hear 10% speed. At idle with the door closed the threshold to perceive it would be ~50%. It's almost impossible for me to get the fan going 100% (215F), but I have done it. I found a secluded spot to do 0-60 runs, but not much more than 100 yards. So I make a run, slam on the brakes, u-turn, another run, slam on the brakes, then stop at a sign where I usually have to wait a while. Then it hits 215, and yes the fan noise is obvious. While not ideal for 0-60, it is a good cooling/fan test, and brake test I suppose.

Note I needed a smog check last year so I loaded the oem tune in the night prior, and the next day on the way to work I literally panicked when it went to 228! I thought I popped a hose or something. Nope, just normal temps. If you can call that normal, and I blame the EPA.
Aside from heat being bad for power, you also have all the parts, rubber, battery etc that don't appreciate it. I especially worry about that rubber gasket between the timing cover and block, which would be an absolute nightmare to change. So I'd like to keep it cooler, and keep pressure on it to a minimum. Not much psi at 195F, but whatever it is at 230 it's much worse. No wonder that gasket fails on people.
Also note; there is another fan control map in there that starts at a lower temp, but my car has never followed it. Other M157 & M278 peep say theirs get hot too, so maybe it's a non-US map? Like maybe it's the map they wanted, but the EPA said no dice so we get the hot one. I'm 100% guessing, but the map is there. I mention it because maybe there's a chance you can toggle to it via Xentry or something, as 51north mentioned. That map isn't as cold as mine, but closer to mine than the oem (below).

The reason your post caught my eye is I had to replace my stat over X-mas and it now runs ~200F all the time, and it's buggin the crap outta me. So I found you while looking for thermostat mods. Specifically I wanted to find the programming for the stats heater control, but so far I've found zero here or the net. Not sure if this new stat is hotter than normal, or my old one cooler than normal, but I want my lower temps back, and ideally lower it more. The heater element is capable of opening the stat just fine, which I can force because it's commanded open when I floor it. Say I'm on the freeway at 200F and I floor it for one second, it commands the stat open. The problem is it takes a bit for it to heat up and respond, and slowly over 90sec later it hits ~165-170. Then seconds later is going back to 200, which takes another 90sec. So it's pointless, but it tells me I could have full control using the stat heater. Not much use to you since you need fan to work first, but fyi.
The fan has a controller power box mounted on it (at least mine does and I assume you do), and I've always wondered if its input from the ECU is voltage or PWM. Makes sense it would be voltage, but MB likes to be difficult, so who knows. My thought was you could check, and if voltage you can amplify it and/or feed it a minimum to net a min fan speed. Maybe 10% which I rekon would mostly fix your problem? If PWM it's still still doable, just a pita in comparison. I had often thought it would be nice to have a button to pre-cool the eng down another 20F before a race or whatever. Especially so if you don't adjust your fan like I did and end up at 230F sitting at a light. Optionally you could control it with a temp sensor to set it wherever you want. Basically just a variety of info in my brain, fyi.

As for the intercooler pump mod; I tried that and it does make a big difference in the temp when putting around, but that didn't actually do anything for me. Obviously it's already on when you floor it, which sounds good, but it's also flowing warmer water. What I saw oem is the IAT was higher at idle and putting around, then under boost it climbs a few degrees right away, then when the pump kicks on the IAT dropped a good bit, then climbs again until I let off the gas. Modded On it is lower temp at idle/normal driving, but doesn't drop in temp when I gas it, instead it basically sits there for a couple seconds before it climbs. It's been a while since I had that mod so I don't remember the exact details, but I do recall my opinion, which it wasn't really any better. Overall there are other negatives to the mod; like drawing a lot of power all the time the key is on, and even for a bit after you turn it off. Plus who knows what it's doing to the pumps life span, which people claim is already too short. So I considered the mod not worth it and undid it...
Later I was able to adjust it with HP Tuners, so I modded a few settings so it comes on sooner when floored, stays on longer after. Imo it's basically all the bennies of oem and modded. I don't believe you can adjust the IC pump on a 2014 using HP Tuners, but you could do the relay mod with a toggle switch, which is what I was doing. I had a teeny little switch under the dash.