Question about a diesel

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Blackbird.

Blackbird.

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Blackbird5150
My buddies car, a 1995 MB E300, is a diesel and it has an issue I'm not sure how to fix. I know that diesels run off of compression not spark like gasoline engines. Before it would shut off all the way but now when you turn the key off it seems to starve for about 2.5 seconds then shut off. Is it an issue with the fuel supply not fully shutting off?
 
Blackbird.
My buddies car, a 1995 MB E300, is a diesel and it has an issue I'm not sure how to fix. I know that diesels run off of compression not spark like gasoline engines. Before it would shut off all the way but now when you turn the key off it seems to starve for about 2.5 seconds then shut off. Is it an issue with the fuel supply not fully shutting off?
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Could be that the injectors need some cleaning, or need to be replaced. How much has the car run?

If they aren't working properly anymore, they don't fully close right away and some drips of diesel still come out.
 
Dennisch
Could be that the injectors need some cleaning, or need to be replaced. How much has the car run?

If they aren't working properly anymore, they don't fully close right away and some drips of diesel still come out.
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He bought probably a month, month and a half ago. Is driven daily now. Right now it has about 162k miles on it.
 
Blackbird.
He bought probably a month, month and a half ago. Is driven daily now. Right now it has about 162k miles on it.
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Definitely the injectors. Only things that ever go kaput on a Merc diesel.

But, before he swaps them for new ones, let him trow some injector cleaner (for diesel) in his tank when it's half full. Maybe some dirt got sucked into the system.
 
I foresee a runaway diesel.

If this does happen put the car push the clutch in all the way, put the car in 5th or 6th, have the handbrake fully up, press the brakes. and slowly release the clutch to slow the engine down before it blows up(i really do mean blow up)

When you get a run away diesel caused by bad injectors or a gasket leaking oil the engine runs of it and starts to increase its RPM, as RPM goes up more oil leaks into the engine making it go faster, then it will rotate faster than it should(redzone and past it) and then BOOM!.
 
Anna+Reece
I think he means, does he not drive it a ton?
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Oh, like I said it is daily driven. 45 miles one way. So long trips yeah.

Grayfox
I foresee a runaway diesel.

If this does happen put the car push the clutch in all the way, put the car in 5th or 6th, have the handbrake fully up, press the brakes. and slowly release the clutch to slow the engine down before it blows up(i really do mean blow up)

When you get a run away diesel caused by bad injectors or a gasket leaking oil the engine runs of it and starts to increase its RPM, as RPM goes up more oil leaks into the engine making it go faster, then it will rotate faster than it should(redzone and past it) and then BOOM!.
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Its an auto.

With what I've read ill try the injector cleaner. The engine leaks no oil.
 
It's more than likely just a bad fuel shut off solenoid or if it uses one, a vacuum leak. My brothers '87 Merc. 300D won't turn off with the key anymore due to a vacuum leak, and the initial systems are what you describe.

I've also been brought multiple trucks with the same issue and each one had a bad FSS which caused it. Bad injectors would have more issues than this, such as excessive black smoke, mad MPG ect. Like I said, I'm not familiar with the exact engine your buddy has but I am extremely familiar with diesels in general.

Edit: Also, 160K miles is nothing for a diesel as long as it's been treated decently. My truck has right at 300K miles with the stock injectors and they look fine. I'm replacing them with bigger ones but I'll definitely be keeping them as back ups.


Parker
 
peobryant
It's more than likely just a bad fuel shut off solenoid or if it uses one, a vacuum leak. My brothers '87 Merc. 300D won't turn off with the key anymore due to a vacuum leak, and the initial systems are what you describe.

I've also been brought multiple trucks with the same issue and each one had a bad FSS which caused it. Bad injectors would have more issues than this, such as excessive black smoke, mad MPG ect. Like I said, I'm not familiar with the exact engine your buddy has but I am extremely familiar with diesels in general.

Edit: Also, 160K miles is nothing for a diesel as long as it's been treated decently. My truck has right at 300K miles with the stock injectors and they look fine. I'm replacing them with bigger ones but I'll definitely be keeping them as back ups.

Parker
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Yeah I know 160k isn't much for a diesel. Point is its a used car and only had it for about 2000 miles. No idea how the car has been maintained.

Grayfox
Best additive I would recommend is BG244 for diesels and BG44K for petrol.
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Are those brands available in the US?
 
Also ,just for fun, if he knows how to, take off the intake and check the inlets. In diesel MB's they tend to be rather clogged up thanks to EGR.
 
They are mainly sold in the UK but their may be some on Ebay or some other auto seller in the US.
 
Alright I have another question. Probably someone who is familiar with these mercedes diesels.

This is my friends car but I commute alot with him so it's kind of in my interest to make sure things aren't going to blow up. :lol:

Here's a picture I took merging on the freeway. The power in this car is pretty terrible so flooring it is basically a must. The picture doesn't show it, the phone took it to slow it looks like it shifted already when it finally took it. But the RPM needle goes way past the 6000rpm mark, seen here:
photobucket-23767-1339352464665.jpg

I just want to make sure this is normal, I figure it would have a rev limiter or something. Can't say i've seen a needle tach out before and then keep hearing the engine rev more before it finally shifts.

Then this picture is it just cruising at... 78mph? It just seems like it's revving pretty damn high. If this is how MB intended it then so be it. I just want to make sure.
photobucket-24976-1339352453624.jpg
 
Any automatic transmission should always shift conservatively. If it normally shifts like a truck in trailer-tow mode then something is wrong with the transmission. The fluid could be bad or low, which might cause a low pressure situation and the transmission to shift later than normal.
 
Keef
Any automatic transmission should always shift conservatively. If it normally shifts like a truck in trailer-tow mode then something is wrong with the transmission. The fluid could be bad or low, which might cause a low pressure situation and the transmission to shift later than normal.
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Well, it usually shifts conservatively but like I said in the picture it's floored.
 
I forgot to comment on the cruise RPM. I'm pretty sure that is absolutely not normal. Count how many gears its using. Sounds like its not upshifting.
 
Forgot to respond.

It shifts four times but I don't think its going into OD. Low fluid issue?
 

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