Mercedes B Class EGR, Glow Plug, Thermostat Replacement and repair W245 W169

Mercedes 2009 B Class glow plug indicator came on. The thermostat needed changing too, and as it turned out the EGR was 90% blocked. Short video of my escapades to repair the car.

[@amwalonline]

The only video on KZbin about Mercedes-Benz b class changing glow plugs. So there is no need for taking off the engine of the car. Well done. Thanks

[@razenby]

You are welcome.

[@tehdreamer]

Very true about the glowplugs, one of mine snapped of course. Turned into a weeks struggle... I got a glow plug removal kit from ebay for £20 or so and managed to get the snapped glowplug out myself without getting the head off.

[@razenby]

Good job. I'm not really that fond of Diesels

[@runner19781978]

Just wanted to say thanks for putting up this vid. It helped me a lot. I was replacing the thermostat. Mine failed the same as yours with the valve coming loose and sticking out the end. The engine wouldn't get hotter than 60 degrees and ran rough at idle. The stat fixed the rough idle. The only issue I did have was after cleaning out a very clogged intake the car wouldn't start. The engine was breathing through three 10mm sized holes through the soot in the intake. Mine was soot rather than the baked on stuff you had. Probably due to the low running temp at 60 degrees. I suspect the non-start was because the fuel adaptions were so far out. After plugging my obd tool and resetting adaptions it started.

[@razenby]

No problem.

[@michaelcurtis7822]

Fantastic video, thank you very much, I would not of imagined any of the difficulty, once again thank you.

[@razenby]

I am please you found it useful.

[@shanesiva187]

thank you lots,,,,,, my sisters 08,cdi(165k) began stopping at any time, , i stripped it down new Gplugs, rail n crank sensors.,thermostat, air/oil /fuel filters, n full clean/ de coke egr, Maff clean, and its all running gr8 again,,, infact much better... many thanks,,,

[@razenby]

Great job. They are such good cars. Ours is still driving like new at 188K. however it had it's second electrical fault just last week. The Bosch alternator stopped charging. If found a suitable set of brushes from the tool store in their brush drawer that fitted after a bit of filing and she is up and running again running on drill motor brushes. We will see how long they last .. The composition seemed very similar.

[@nbdcbn]

about to do this after taking the whole engine and gearbox out replacing tons of things only for the EGR valve to be cocked up. Thank you for the video

[@razenby]

Thanks. Soundd frustrating.

[@nbdcbn]

@@razenby it was one hell of a learning curve but now I know more than the average garage from how much I had to read on these engines and change things hahaha

[@V6Greg]

Very helpful video thanks!Replaced glow plugs on W169 A180 CDI using this!

[@razenby]

Glad it helped. Thanks for watching.

[@grahamroberts696]

Thanks for this I've just changed the thermostat on my b class. The Egr valve was cruddy. Now just need to change the starter motor

[@razenby]

Good Job. they are fantastic cars. Underrated I think.. Ours has done 150K miles and is just started to loosen up and provide more power. Parts are really cheap.

[@nigelwells7352]

Very well done Sir and thank you very much.

[@razenby]

You are welcome.

[@nigelwells7352]

@@razenby hi again wonder if the words "glow plug replace" had featured at the beginning of your post, whether many more would have seen it. i searched many times for a post with such wording but to no avail. once again great stuff and thanks.

[@yannisstefan9066]

Fantastic video, definetly going to check my glow plugs on my b200 cdi in a few days. The glow plug light comes up from time to time and after it comes out there is a one second delay on the acceleration and when it does accelerate it jerks. Thank you for the video, it's the only one that goes in detail about the steps to get to the glow plugs.

[@razenby]

*But first check you battery is healthy* A bad glow plug can cause erratic or difficult starting but once running doesn't adversely affect engine performance. The jerk at pick up is unlikely to be caused by the glow plugs the combustion self-heats the glow plugs. It may be an indication of another electrical fault triggering a and error on the glow plugs. Do you have a code reader? You may find other related electrical fault codes which will indicate wider problem. If the battery voltage drops too low during starting then strange stuff can happen. Also check the earth bonding strap located at the back end of the gearbox underneath the car. This can crack or come loose causing weird stuff to happen.

[@drvotransd.o.o.2405]

Thanks for this tutorioal!

[@razenby]

No problem.

[@flavoursonly]

Absolutely outrageous 😂 all this for 4 glow plugs and a thermostat Mercedes really want you to bring it to the “workshop” for this one haha

[@razenby]

It is a faff getting to them. I suppose when it is not all bad when you consider that the car has now done 180K miles with no breakdowns and just this single service to the top of the engine. Still on original water pump, aux belt tensioner pulleys and cam chain. Nothing else has been changed. Great car,

[@flavoursonly]

@@razenby one of the most reliable Germans of its time for sure. Your gearbox if it’s CVT is still going on 180k 🤣🥂. You must of serviced it at least a few times

[@Shihtzu_aventures]

thank you

[@razenby]

You are welcome.

[@florrieflorrie8342]

Magic smoke good video and just wondering after all that work why you didn't put a blanking plate on the inlet to the EGR valve , I've got the w169 with 120,000 on the clock no lights up on dash but you know it's gummed up. My mechanic says block it up it will damage the engine so for now I've got a another EGR valve off eBay and put it under the bonnet and swamped the vacuum pipes and it works a treat.

[@razenby]

Conscience about the environment. The B class now has 145K miles on it and it still runs and drives like new. These are seriously underrated cars. Most mechanics don't know their arse from a hole in the ground. They are great with spanners but weak on theory.

[@MaxiTech]

w169 A class has the same engine, please add this to video title too. thanks for this

[@razenby]

Added, thanks,

[@bodowoyde455]

great explanation, thank you for sharing! agree, "someone was on accid when designing this car" with "mysical Mercedes pipework" and "tonns of spaghetti on top of the engine" - lol btw is the engine comming from Mercedes or from a cooperation with Renault?

[@razenby]

Thanks for sharing

[@magnusbondesson6301]

Thanks so much for doing this video! Helped me a LOT!!!

[@razenby]

Glad it helped! There isn't much info out there about the B class engine.. Car is still going at 185k miles.

[@camillosteuss]

Nah, its true, i worked as an apprentice in a shop, under the mercedes guy, and as a merc guy myself, it was a pleasure to learn from him... The one thing i do remember was one of the few cases of broken off glow plugs in that same engine, just in a w169(second gen a class)... I had to go out and buy a hssco10 drill of 5mm to drill a hole into one of these bitches after the top snapped off... I took a left hand drill, as i hoped that it would maybe catch and we could get the plug to unscrew thusly, but in the end, we tapped a thread into her, left hand aswell, and by tightening the screw, the right hand thread of the glow plug let go and the damn bitch was finally loose, after 2 hours of messing with it... We tried everything, but in the end, making a quick jig to guide the drill was the only option... You dont want the drill to walk off and obliterate the threads in the bore, as that is an even worse thing to have to report to a customer, and the design of the plug really encourages the drill to wander anywhere other than to go straight down the center due to the construction of the plug itself... I would have thought you would have cleaned out the intake manifold and the whole egr region, as that gets caked up like hell over time... So much so that i have seen manifolds with like 80% of the supposed internal volume of the manifold being just caked up oily soot due to our just brilliant egr systems... You know that shit can either break off and fall in the cylinder in chunks or it can just slowly build up until you have almost 0 air passage, suffocating the engine, reducing the efficacy of the engine and its fuel efficiency, just torturing the whole system for no good reason... Either way, when you came this far, you should really have taken the manifold and egr off, tossed both into industrial degreaser for a day and rinsed those out well... Hell, you could even consider the weight loss of all the dissolved carbon and oil slag a performance gain in more ways than one... Sure, its not a lot of mass compared to the mass of the car, but having 300-500 grams of oily soot in the intake manifold which is meant to hold nothing but air in a hollow passage is a really good mass loss... People go polishing and porting their intakes and do the port matching, but this baby right here makes her own variable port geometry by getting caked up like a crapper after a bad exotic cuisine experimentation... And if you let her sit until now, its only gotten worse... I am in the process of taking my own w169 apart for this very reason, and i wanted to see if anyone has posted anything like this... Sure, im 4 years late to say this, but then again, if this helps anyone, great... The video is great enough as is, given the madness that is the slant engine design of the a/b classes(and some other vehicles, look up the diesel engine, it goes in everything, from vans to cesna`s)... Tho, despite being a pig to work on, and a complex pig at that, she is a good engine in my experience, as well as are the a class w168 and w169 generations... They are quite old now, and other than few universal rust congregation spots on those, if maintained even a bit well, both generations seem to be a great car, and i own both, and both serve me perfectly, other than the few characteristic bugs they develop... But nothing major, and i did almost flip the w168 in the elk style once... Ended up on two right side wheels, but i turned the wheel to the right and she fell back onto all 4 before i needed to correct the steering... It was an even shielded by the Providence, as im still alive, and i was going 55mph then or around 90km/h... But i also managed to flip a clio gen 2, the renault... I had it while i was working on my w168, and well, i outdone my self, given that im still alive and i managed to slow the 45mph clio before it hit the ditch and flipped over down to like 17mph... The wheels lost grip on an oily patch of road, but there are ways to slow down a car if you know how to drive it like a savage beast just for fun everyday... Never was I more glad than then to be a madman behind the wheel... Tho, that was also sponsored by the Providence, as those 2-3 seconds of time i had appeared like a minute, allowing me to position myself for the crash, preparing the feet and all other body parts into safe arrangement, yanking the belt to lock it in place, pushing the head back against the headrest and so on... well, im alive, the clio aint, and well, lets just say that i would advise anyone an A class w168 over a clio second generation any time of the day... Not because im a merc lover and a merc mech, but because the clio gen 2 is really a steel coffin waiting to plow you into dirt... All the best, and sincere apologies for the bible long comment...

[@razenby]

Thanks for the comment. It will useful for owners.

[@axleg3737]

Thanks so much a lot of work and so much for this video. what brand of glow plugs did you use?

[@razenby]

I got them from Eurocar parts (Starline). I wish I hadn't as one of them blew in a few months, I put one of the working OEM ones back in and they are still going at 188K miles........

[@axleg3737]

@@razenby Thanks again

[@abyssaldision5134]

Hi, Can you tell me where are the injectors located on this engine?

[@razenby]

At the front of the engine. See this picture dalys.lt/en/autoparts/mercedes-benz/b-class-w245-b-180-cdi-245-207-80-kw/engine/1251661

[@leerdoor]

Do you use WIS/ASRA for instructions? By the way, do all people in the UK have car lifts in their backyard? :‑D

[@razenby]

Hi, No - just the workshop manual. On this car there was precious little information in the wild. I couldn't even find out online where the glow plugs were located. Great car - still drives like new at 170K miles and counting. The car lift was about £1000 (GBP), In the family we have 6 vehicles. I don't spend on mechanics fees - I just don't trust them, and I don't waste money on vehicle depreciation either. Fees are eye-watering. I only use the lift now and then but it has paid me back in spades. The only trouble is you discover that you have a lot of new friends when you get one!

[@kanisixos]

@TomatoLove about belt noises. simply use,(Contitech) belt. 👍

[@chrisbluck7276]

Absolutely brilliant video, Thank you. The thing you called an air mass throttle thing, what is the actual name of it please? My son has just bought an A class, same engine but the pipe that goes into that keeps popping out. It looks like the clips are broken so I need to replace the whole piece and I cannot find out the name of it. Thank you again for the best Mercedes video out there

[@razenby]

The bit that usually pops out is the air pipe post turbo that fits in the 'Mass Airflow Sensor' is at 7:52 in the video. Are clips installed. There is a lot of force from the air inlet boost pressure when the turbo is active. The clips stop the wire ring slipping out of the groove. I would probably get the assembly with intake pipe and MAF from a reputable breaker. These days they tell you the year and mileage of the donor car. Parts are surprisingly cheap. In my view used OEM parts from a 70K miles car are better better than new aftermarket equivalents. Our car has done 180K miles with no MAF issues at all.

[@chrisbluck7276]

Awesome, thank you. I've taken it apart today and hopefully fixed it. I will take it for a test soon but if not then I'll grab those bits.

[@chrisbluck7276]

@@razenby and no, there was one small clip but the bottom one wasn't there and the big main clip had snapped at one of the ends. It was still a bugger to get off though, lol. I've just out an adjustable clip on it and tightened it as much as possible.

[@razenby]

@@chrisbluck7276 Ahh OK. get any assy from the breaker..

[@chrisbluck7276]

@@razenby I haven't even looked yet. Most are shut around here until Monday. But it seems absolutely fine on the test drive. The glow plug light went off and then came back on, along with the EML, so we've just bought some plugs and I'll fit them tomorrow. Really not looking forward to it.

[@romannozheyev7611]

Спасибо братан!

[@razenby]

Без проблем

[@soto575]

So i have to change 1 glow plug in the same car do you recommend changing 4 and the thermostat ? Plus i have to change the radiator and it's seems its a big jod too .

[@razenby]

It depends. I changed all for with aftermarket glow plugs and one of them failed within 18 months. With hindsight I would have just changed the faulty one. I put one of the working old ones back in and it is working fine. Definitely worth changing the thermostat and cleaning the EGR and mixing channel whilst you are in there. My B class still going strong at 180K miles. Drives like new. Good luck.

[@flavoursonly]

@@razenbywhat brand glow plug did u use that failed in 18 months?

[@Norwayplayer95]

How did u remove the air intake to the turbo tube? I removed both of the clips,but no chance removing it...

[@razenby]

It is a wire that you need to pry open. I use O ring picks to get behind it and lift it.

[@Norwayplayer95]

@@razenby oh right, thanks

[@WhosLeadingYou]

Ok, so I have done whole thing, replaced all 4 Glow plugs (snapped one but managed to get it out with a screw/bold extractor) and the thermostat, now insteat of the temp fluctuating it just remains hot like 95 degrees or there abouts. any ideas? the front fan doesnt seem to spin up, maybe its that? or the water pump? how can you tell and how do you test these compontents, im stuck.

[@razenby]

When the thermostat is working the temperature will not fluctuate but will read low when engine is cold and move into operating position was the engine warms up and then stays there. Once warmed up, on my B class, the gauge hardly moves whatever the weather. With a cold engine, if gauge registers high as soon as you turn on then it is likely a wiring or sensor fault. I have not experienced any airlocks. Check the sensor is plugged in. If the fan fails to cut in then check the sensor, fan motor and wiring. Keep you hands clear, if the fan starts with your fingers in the way it will cause injury. If you engage aircon the fan should start immediately. (providing your aircon works. I hope that helps.

[@WhosLeadingYou]

@@razenby It doesnt stay at 95. it starts off normally eg cold, but once it starts to heat up is keeps going till 95 and stays there abouts so I dont think its the temp sensor. Just tested the fan with the air con as you mentioned and it started up as it should.. so now Im left thinking it's the water pump. I found the auxillary waterpump and that operates fine but do you have any idea where the engines main pump is and how to test it? Thanks for all your help, much appreciated.

[@razenby]

@@WhosLeadingYou Main water pump is driven by the Auxiliary belt. They either work or leak. I doubt it is the pump.On our Merc it sits about half way between 80 and the 120 mark. Why don't you just check the temperature? What temp were you expecting I believe 90 degrees is about the right temperature for a pressurised system.

[@WhosLeadingYou]

@@razenby Really? I just assummed that 80 degrees was the correct operating remperature as the thermostat is listed as having an operating temperature of 80 degrees and most cars in my experience have the temp gauge pointing to the middle temp. The fact that your car seems to operate at a similar temp to what im seeing to my car does provide some comfort. Im just concerned that it may not be that good for the car in summer here in Western Australia when we often get temeratures rising in to the 40's. Thank for your help, Im just going to leave it for now and keep an eye on it. You're video has been such a blessing to me we need more people like you making helpful videos like this, make my life so much easier.

[@tincan6929]

Takes me back another mercedes smart nightmare someone on acid designed it lol

[@razenby]

Oh I love our B class. 220K Miles from new and never been ever been to a repair shop mechanic or a Mercedes garage. Still drives like new.

[@olivertwist9003]

May I have the name of the forum? As I just got my B class recently, and try to do routine maintenance myself.

[@razenby]

Hi Oliver. What model year and engine do you have? For routine stuff just refer to a Haynes manual. On the W245 diesels there are a few simple faults that have happened on the cars that can be prevented by inspection. Sheers.

[@olivertwist9003]

@razenby Thanks very much, it's a 2011 B class 180 diesel w245.