30,000 miles no oil change,
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1991 190E 2.3
You'll need to solve your brake issue first for sure but once you've done that take it back out on the highway and keep repeatedly stomping on the accelerator pedal. My engineer father would do this with our cars as a way to deal with carbon build up. No doubt your car probably still has a lot of crude built up. It'll probably smoke and carry on for awhile but eventually it will clear if you keep doing it enough.
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From: Panama City, FL
2020 C300, 2013 C250, 2000 Boxster S
Low and middle rpm stumbling combined with brake issues would seem to point to a vacuum leak somewhere. Vacuum issues have less of an effect at high rpms.
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From: Orange County
c250
its weird... I just went back to the car and did a cold start... back to smoking like crazy, and the brakes work fine... the car already had its entire intake manifold replaced by Mercedes... Tomorrow night or morning i'm gonna give it a drive again since its behaving just like it did this morning with the smoke at first and crap mid range rpm.. I am so confused on what happened to this car. After my drive I'm going to change its oil/ filter (its already fillllthyyyy) and re-inspect for vacuum leaks but honestly... all the hoses look perfect and there is nothing obvious. and for the previous posts, I am 100%% sure the head gasket is perfectly fine. And considering the car runs with no smoke once i beat the crap out of it I'm ruling out piston rings and valve seals. anyone have any ideas?
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From: Orange County
c250
I had to make the same decision at the beginning of 2019 and I decided to try and save the engine - that had gone a little bit over 50K miles without an oil change. It took me about a month and a half to complete the job from start to finish - working on it in my spare time never longer than 2 or 3 hours a week. The job was pretty straight forward if you are somewhat mechanically inclined. The total cost was something like $1500 parts/tools as I was able to clean and reuse almost all the original parts. Its been 10.5K miles since the repair and the car has been running flawlessly - so i can say I succeeded.
The simplest solution would have been to buy a used engine from a wrecking yard and put that in but I figured since it was already "broken" I might as well give it a shot as I could not make it worse.
What I would tell you is do the tear down to block, inspect all the parts for wear and tear, warpage, scoring and the like. By the time you get to the pistons you should know whether it is worth your time and money attempting the rebuild.
My rule of thumb was since it was running before i started the teardown then it has to run after I rebuild it as long as I do everything correctly.
The simplest solution would have been to buy a used engine from a wrecking yard and put that in but I figured since it was already "broken" I might as well give it a shot as I could not make it worse.
What I would tell you is do the tear down to block, inspect all the parts for wear and tear, warpage, scoring and the like. By the time you get to the pistons you should know whether it is worth your time and money attempting the rebuild.
My rule of thumb was since it was running before i started the teardown then it has to run after I rebuild it as long as I do everything correctly.
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From: Upstate NY
2013 C250 SPORT, 2014 WRX STI SEDAN, 2017 E300 4MATIC
So This morning I went on a drive. Lots of smoke at start up and no smoke there after. Car has a really bad misfire at idle and at 2500-3200 rpm. After it runs fine but the car is definitely low on power. The brakes are still rock solid with no assist but I just pushed really hard on them and the car would stop. I cant see any noticeable vacuum leaks under the hood but when I disconnected the brake booster with the engine running the suction on the hose was weak and I barely felt anything at all sucking in and also the idle didn't change at all and it was still idling badly. Is it possible the entire cause of the oil smoke and bad brakes and vacuum leak this entire time was the vacuum pump?
Vacuum pump only affects brakes - would not cause your idling problem.
Is the car throwing any codes? if it is what codes?
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From: Orange County
c250
Your smoking problem is coming from oil leaking into the cylinders through valve stem seals. I happens at startup mostly because when the engine is not running the oil lubricating the cam/lifters/cans starts to settle at bottom of head and will find its way into the cylinders due to the leaking seals. When the engine starts running less and less oil makes it into the cylinders and you get less or no smoke. When you turn off the engine the cycle repeats and you get smoke on start up.
Vacuum pump only affects brakes - would not cause your idling problem.
Is the car throwing any codes? if it is what codes?
Vacuum pump only affects brakes - would not cause your idling problem.
Is the car throwing any codes? if it is what codes?
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Joined: Nov 2008
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From: SA
2008 C350-Sport-AMG-Active Agility Pack(Not reliable) +Izuzu KB6 3L(It seems Reliable)+Mazda
From what I have seen it looks synthetic oil is good if you replace it regulatly, if left it gungs up everythig. I seen old vehicles with mineral oil standing for years, look ok on the top but sludge in the sump.
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From: Upstate NY
2013 C250 SPORT, 2014 WRX STI SEDAN, 2017 E300 4MATIC
the car is throwing cylinder 2 and 3 missfire codes along with an engine reduced power program code. The car idles really rough and low, when accelerating it jitters and stutters and missfires at 2-3000 rpm ALOT and thereafter it revs to redline just fine. The brakes work but there is no assist at all, Pulling the hose off the brake booster I noticed the suction is extremely little at idle. Taking off from a stand still is really hard and it feels like the car is in some sort of limp mode. When in drive or especially reverse while backing up slowly with the steering wheel turned the engine missfires so badly and runs so rough the entire car shakes terribly.
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Thread Starter
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From: Orange County
c250
Member
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From: Upstate NY
2013 C250 SPORT, 2014 WRX STI SEDAN, 2017 E300 4MATIC
If your timing is good it means chain and tensioner are also good.
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From: Orange County
c250
Pull the coils again. Make sure you have no oil leaking into the plug wells and that coils are perfectly dry. If those check out then pull valve cover and check your timing chain and valve timing. The chain tensioner on this engine is hydraulic- so it can fail too due to lack of oil changes and the timing chain could have jumped a tooth or two.
If your timing is good it means chain and tensioner are also good.
If your timing is good it means chain and tensioner are also good.
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1991 190E 2.3
Sounds like you're getting close but at this point I would suggest holding off on beating on the car anymore until you get the new parts installed. It looks like the sludge build up is pretty significant so that likely explains the oil burning. Once the new parts are installed and there are no more error codes, then take it out on the highway and beat on it for awhile to continue to dislodge the remaining sludge. Eventually the oil burning should stop. Be sure to keep checking the condition of the oil and filter until they no longer show signs of sludge. I think it's great you've taken this project on as I think this car is worth saving. Bravo for doing so. It must be nice that someone had the financial resources to run a $40,000 car into the ground. That's certainly not in my budget or most people's budgets. Their stupidity is your gain.
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From: Upstate NY
2013 C250 SPORT, 2014 WRX STI SEDAN, 2017 E300 4MATIC
Ok so I cleared my codes and went on a 70 mile drive. The only code that came back was a cylinder 2 missfire. swapped cylinder 2 with 3 coils, Code became a cylinder 3 misfire. I ordered a new ignition coil. The vaccum pump is dedicated for the power brakes and my power brakes don't work. I ordered a new vacuum pump. Last night I gave it another oil change. In less than 100 miles the new oil and flush became DARK and ruined, and the brand new filter was now disgusting and all the filter was full of sludge chunkies. Not great, but clearly the engine is getting cleaner so no complaints there. I put new oil, more flush, and a new filter. I plan on doing that at least one more time. This leaves me with the last issue. The oil smoke. the car isnt nearly as bad as it used to be. But about 1 or 2 minutes after turning it on it will put out lots of burnt oil, and then after warming up it will not smoke at all, especially when accelerating. but even when the engine is hot at idle it might give a little smoke. does that sound like valve seals? not sure. But I want to fix that oil burning issue as its probably ruining my emissions system, and its embarrassing.
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From: Orange County
c250
There is only 2 ways for oil to get into your cylinders. One is through the stem seals and another through the piston rings. You can rule out the rings by doing a either a compression or a leak down test. If that fails - you have to pull the engine to fix or replace it. If it passes then it is definitely the valve seals that are leaking as there is no other way for oil to get in the combustion chamber.
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From: Upstate NY
2013 C250 SPORT, 2014 WRX STI SEDAN, 2017 E300 4MATIC
I don't think the smoke will go away on its own. If the smoke does not bother you and the car passes emissions then I guess you can keep driving it. Not sure what the long term implications of driving the car with leaking seals are but I assume the seals will continue to deteriorate and the problem will get worse.
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From: Orange County
c250
I don't think the smoke will go away on its own. If the smoke does not bother you and the car passes emissions then I guess you can keep driving it. Not sure what the long term implications of driving the car with leaking seals are but I assume the seals will continue to deteriorate and the problem will get worse.
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From: Orange County
c250
I don't think the smoke will go away on its own. If the smoke does not bother you and the car passes emissions then I guess you can keep driving it. Not sure what the long term implications of driving the car with leaking seals are but I assume the seals will continue to deteriorate and the problem will get worse.
I cleared the codes and the engine seems to be running fine but who knows
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From: SA
2008 C350-Sport-AMG-Active Agility Pack(Not reliable) +Izuzu KB6 3L(It seems Reliable)+Mazda
Just thought, what would happen if your feul pump sucks air but not always from somewhere, maybe going through a rough patch of road-? What did they battled with before you bought it, why was it parked-?
Last edited by Moto_Guzzi; Oct 19, 2020 at 01:57 AM.
Thread Starter
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From: Orange County
c250
I don't think the smoke will go away on its own. If the smoke does not bother you and the car passes emissions then I guess you can keep driving it. Not sure what the long term implications of driving the car with leaking seals are but I assume the seals will continue to deteriorate and the problem will get worse.
Member
Joined: Nov 2010
Posts: 121
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From: Upstate NY
2013 C250 SPORT, 2014 WRX STI SEDAN, 2017 E300 4MATIC
I changed the brake vacuum pump. I got my power brakes back. success, and after filling the tank getting the car to recreate the any problems didn't work, No check engine light or anything.. So at this point everything about the car is a clean sorted mercedes except the smoke, Heres the thing about that smoke. it only smokes 2-4 minutes after a cold start. never on a warm start and never immediately after starting. After I cold start the car at the 2nd stoplight ill look at my rear view mirror and see a CLOUD of smoke. After i hit the gas pedal tho its over. this raises my question. It can be piston rings or valve seals that introduce oil into the engine directly, But Can it be the Turbocharger? It just doesn't make sense how the oil seals would be so specific with their leakage.
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From: Orange County
c250
Do you know of any guide or vmanual available for the job?
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From: Upstate NY
2013 C250 SPORT, 2014 WRX STI SEDAN, 2017 E300 4MATIC
No unfortunately I do not have a guide or know of one. I bought a copy of the WIS from ebay and installed it on old laptop but I did not end up using it at all as it was quite hard to navigate.
If all you doing is replace the stem seals then it should be straight forward. Basically you have to remove valve cover, top cam cradle, sprockets, cams, cans/lifters and at this point you are at valves. You need a special tool to compress the valve springs and and change the seals. Then put back cans/lifters, cams, cam cradle, set timing, put back sprockets, chain and complete the reassembly.
Read the thread below. I tried to include most of the important parts. There is also a couple of YouTube videos on head gasket work on the m271 engine, our engine is a different evolution of the m271 but it is still basically the same - watch those and then decide if you think you can do it.
https://mbworld.org/forums/c-class-w204/739350-c250-sport-no-oil-change-6-years-50k-miles.html
If all you doing is replace the stem seals then it should be straight forward. Basically you have to remove valve cover, top cam cradle, sprockets, cams, cans/lifters and at this point you are at valves. You need a special tool to compress the valve springs and and change the seals. Then put back cans/lifters, cams, cam cradle, set timing, put back sprockets, chain and complete the reassembly.
Read the thread below. I tried to include most of the important parts. There is also a couple of YouTube videos on head gasket work on the m271 engine, our engine is a different evolution of the m271 but it is still basically the same - watch those and then decide if you think you can do it.
https://mbworld.org/forums/c-class-w204/739350-c250-sport-no-oil-change-6-years-50k-miles.html
