[ddcasey]

My GLA 250 4-matic suddenly overheated- warning light came on saying "engine coolant temperature dangerously high". Car was towed to dealer. After 5 days I was told the water pump was the culprit and needed to be replaced. The car has 6500 miles on it. They replaced the water pump but told me the malfunctioning one visually looked fine. Nothing broken, no worn bearings, no obvious leak. I heard nothing in the engine prior to the overheating and did not notice any leakage of fluid in the driveway. Obviously I am not happy about this- engine failure at 6500 miles with no good explanation does not bide well. Apparently they have seen this issue in 3 CLAs- one at 30k, one at 15k, and one at 5 k miles. The dealer never got feedback from Mercedes as to what the issue was with the failed water pumps. How do I know this won't happen again? I don't feel comfortable driving this car far from home as I still don't know what the problem was. Anyone heard of this issue in GLAs?

 

[cute-ute]

You may have experienced the first water pump failure on this forum because I couldn't find any mention of the GLA's water pump breaking down here.
Maybe ask your dealer to follow up with Mercedes about the pump.

 

[ddcasey]

Yes I asked the dealer to get follow up from Mercedes, but they said this may take a few weeks. The mechanic at the dealer said the water pump from the CLA/GLA was a new design- much smaller than previous water pumps. I suspect some sort of design flaw that led to failure.

 

[cute-ute]

New designs usually have issues crop up here and there but let's hope that yours was just a random faulty one and that this won't become a common occurrence.

 

[Oceansol]

I took my GLA250 for a thousand mile drive through the Mojave desert of California (107ºF) up through the high Sierra (8,000 ft), back down through the central valley (sea level, 106ºF) then down the coast of California back to San Diego, with 4 adults and a week's worth of luggage this past summer with no issues whatsoever. Sorry for your failure, but hopefully this was an isolated failure.

 

[jlipinski3]

Just had this happen to me. Car was being hesitant to shift out of 3rd, then 4th, and about 90 seconds later coolant meter went all the way to the red and got the "coolant too hot, pull over and shut car off" or something like that on the dash. Roadside assistance towed it to Mercedes Westwood and I ditched the car and took an uber home. Waiting to hear from the dealer. Such a pain in the a$$. I love the car but I've been in/out of the dealership about once a mth for the past 6mths. O2 sensor, pebble stuck behind the heat shield, 2 nails in the runflats, "special" coolant top off...it drives me nuts.

 

[turbolink]

Just had this happen to me. Car was being hesitant to shift out of 3rd, then 4th, and about 90 seconds later coolant meter went all the way to the red and got the "coolant too hot, pull over and shut car off" or something like that on the dash. Roadside assistance towed it to Mercedes Westwood and I ditched the car and took an uber home. Waiting to hear from the dealer. Such a pain in the a$$. I love the car but I've been in/out of the dealership about once a mth for the past 6mths. O2 sensor, pebble stuck behind the heat shield, 2 nails in the runflats, "special" coolant top off...it drives me nuts.

That's pretty alarming. Can you share a bit more information...do you have a GLA45 or 250? AWD? Curious if you picked up any worthwhile information during the service process that the rest of us could benefit from. Thanks!

 

[Boxster986S]

I wonder if it's an actual water pump problem or an electronic "ghost". The reason I propose that is an odd gauge malfunction I experienced. Two months after I took delivery of my GLA250, the fuel gauge dropped to zero when I knew it was 3/4 full and fuel range showed zero. A few hours later the reading returned to normal and it has not repeated the problem.






I noted at the top of this chain that the dealership replaced ddcasey's water pump, but could find nothing physically wrong with it. What if the water pump is working fine physically, but the temperature data is either misread or misinterpreted? I would think that the dealer's diagnostic would look for that, but who knows?

 

[Kcgla]

I wonder if it's an actual water pump problem or an electronic "ghost". The reason I propose that is an odd gauge malfunction I experienced. Two months after I took delivery of my GLA250, the fuel gauge dropped to zero when I knew it was 3/4 full and fuel range showed zero. A few hours later the reading returned to normal and it has not repeated the problem.

Funny you should mention that - right after I was reading this thread last night on my way back from work I noticed that my temp gauge was flucuating a lot going down from 90 C to 70C and back again to 100 C and then down again to 90 C (where it's normally at when stable). All of this during a 20 mile highway commute at a temperature of 48F and speed of 72 mph with 2000 rpm on ECO mode. Pics attached. Today much colder but gauge is stable at 90 C.

 

[Kcgla]

Been looking online to see if anyone else has experienced this and there have been reports of faulty thermostats. Today my dealer said that the 20 degree fluctuation is normal. Kind of sceptical about that though. My impression is that the gauge should always register 90 degrees and shouldn't vary regardless of outside temp or speed and cold air intake.

 

[rvittori]

FWIW

When I had my CLA250 with the M270 engine, normal for me was a lot of fluctuation in the beginning of a drive. Temp would go up and then when the thermostat opened it would go down and then raise back up. If I tuned the heater on, I would see more fluctuations. After awhile it would be steady at 90C. The fluctuations were more noticeable in the winter of course.

On my GLA45 with the M133 engine, ten just keep climbing and then holds steady.

 

[jlipinski3]

That's pretty alarming. Can you share a bit more information...do you have a GLA45 or 250? AWD? Curious if you picked up any worthwhile information during the service process that the rest of us could benefit from. Thanks!

2015 GLA250 4Matic with just under 26k miles, stock except for heated seats and panoramic roof. It was the water pump. Had to be towed (free), and was able to pick the car up the following evening. Looked like they had to replace 2 gaskets and the water pump. The writeup said they checked transmission codes, ensured nothing was wrong there, and did the repair.

Definitely a concern to me...I've been very, very good to this car. What happens when warranty runs out at 50k miles? I hate having to think about getting an extended warranty already.

 

[ddcasey]

Almost one year later and car running fine with new water pump, so it does not appear that my issue was related to a sensor problem.

 

[dkmillerii]

Thanks for all the information in this thread!!

Our '15 GLA 250 has 61k miles on it and we got the "overheating, turn off engine" warning today.

Called the dealer who said to have it towed in, probably the water pump.

I will update once I hear the verdict, but the problem manifested as everyone else.

I can tell you for sure though, it was overheated. The coolant overflow was practically bursting at the seams and hot enough you couldn't even touch the reservoir.

Don in Baltimore

 

[turbolink]

Thanks for all the information in this thread!!

Our '15 GLA 250 has 61k miles on it and we got the "overheating, turn off engine" warning today.

Called the dealer who said to have it towed in, probably the water pump.

I will update once I hear the verdict, but the problem manifested as everyone else.

I can tell you for sure though, it was overheated. The coolant overflow was practically bursting at the seams and hot enough you couldn't even touch the reservoir.

Don in Baltimore

Welcome to the GLA forum Don. 61K on a 2015 model is quite a feat. Before you wring your hands too much however, it could also be a thermostat, much less dreadful to deal with. Have had that happen to me many years ago with an Oldsmobile V-8, felt like a volcano about to erupt, shook the entire car. I let it cool, drove to a nearby Firestone, $25 parts and labor, and we were good to go (1985). I guess your mileage takes you out of warranty? Good luck, please let us know.

 

[rtgla]

Another Waterpump failure

I experienced overheating yesterday when I was driving at Eco mode on a city road at 1500 rpm. I checked coolant and leak, everything seemed normal. Car's heater was doing good so seemingly no termostat issue. The only remaining possibility would be waterpump mulfunction! I phoned dealership and will tow the car there. Will update on this topic as soon as find out whats going on.

 

[turbolink]

Welcome to the GLA forum rtgla, sorry to hear about your bad experience. Did you actually get the rumble-type, steaming condition, or just a caution light? Let's hope it's the latter and a simple sensor issue. There are many who will be eager to hear how your case turns out, please keep us posted!

 

[Mark Mainguy]

I just got my GLA back from the dealership yesterday. Coolant pump failure. 60,000 km. It happened in cold conditions, after being parked for 3 days at the toronto airport.

 

[Diane Scuderi]

my temp gauge suddenly went all the way to HOT red area. I just left my house and the notification came on "car is too hot turn off engine" as I continued down the road to pull over it stopped and came down to a normal temp. Few minutes later back to the notification of turn off engine. I am thinking thermostat problem, when I arrived at pep boys the coolant was full. thoughts?

 

[turbolink]

You don't mention which GLA model and year, nor location (Pep Boys sounds like US), but you report symptoms of a sticking thermostat. However, our GLAs, and MBs in general, also have a tendency at times for bogus sensor readings for a number of various reasons. Is your GLA still under warranty? Perhaps the best option for hopeful peace of mind is taking it to an MB dealer to determine if any error codes are in the recent record, and also to ensure MB-approved parts are used if necessary.