my car failed me this morning, I am trying to narrow down what is wrong.

I was driving, about 3 mins away from home and all of a sudden the engine cuts out and would not start anymore. MB roadside assistance was not able to jumpstart with a battery pack nor a fresh battery.

Could the alternator be damaged from a v belt that is too tight or a smog pump pulley that is broken? right now the car is cranking very slowly, even with the fresh battery and battery pack.

What kind of car? M103 is in a few different models.

You say the motor cranks slowly..... Typically this is electrically related - bad ground or corroded battery terminal or wire. Seeing as how a new battery (is it still in there?) didn't fix the issue, I would check the battery cables very carefully and replace them if in doubt. As they become corroded, they lose the ability to carry current, even though the voltage is fine until you crank. The added resistance drops the system voltage when any significant current is drawn.

Sounds like your bad connection caused your voltage to drop until the engine died because you weren't charging adequately. The new battery didn't alleviate it because the connection is too poor to allow sufficient current for cranking and voltage to operate the computers and ignition.

That's my theory, anyway. If it isn't an electrical issue, then your motor is trying to seize up............

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-tp


1990 300SE "Corinne"- 145k daily driver - street modified differential - PARTING OUT OR SELLING SOON - PORTLAND OR. AREA - PM ME FOR DETAILS
1988 560SEL "Gunther"- 190K passes anything except a gas station
1997 S420 - 265k just bought it with a rebuilt trans. Lovely condition

my car is a 1993 190e 2.6

I checked all electrical connections and they looked good to me.

I had interesting results tonight after letting the car sit all day while I was at work. I tried starting it up again after checking the electrical connections and noticed the crank was very strong and the engine actually started but was way below idle and grunted alot and finally died when i let off the throttle.

i called someone over to crank while I examined the engine and noticed there was smoke poofing out of my smog pump (wtf?) could something be plugging up from my smog pump? I know this smog pump is failed and broken, but I haven't gotten around to visiting a junkyard to grab another one yet.

after about 5 tries to start the car, the battery was weak again.

anyone have some good advice before I rip apart my exhaust system?

Take/cut the belt off and see if it starts fine. If so, then you know you have a dragging/locked accessory. You can also spin stuff by hand... I bought my 300SEL with a locked A/C comp.

Furthermore, I would just remove that air pump. I did. It is just for cold starts and more crap to fail.

Pull the alt and check it out. Remove volt regulator and inspect brushes. If they are okay have it tested at a local auto store.

Sounds like you have a few issues all at once.

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I'm not a doctor, but I'll have a look.

'85 300SD 245k
'87 300SDL 251k
'90 300SEL 326k

Six others from BMW, GM, and Ford.

Liberty will not descend to a people; a people must raise themselves to liberty.[/IMG]

i would remove the smog pump completely, but i live in CA and I need it for visual inspection every 2 years. believe me, this would be one of the first things to go if I had the chance, dont feel like swapping idle tensioners and belts every 2 years for examination.

Then install all the early accessories like I did. No one will ever know the difference. I will look to see if I have my air pump, if so you can have it. I think I tossed it though.

__________________
I'm not a doctor, but I'll have a look.

'85 300SD 245k
'87 300SDL 251k
'90 300SEL 326k

Six others from BMW, GM, and Ford.

Liberty will not descend to a people; a people must raise themselves to liberty.[/IMG]

what do you mean install all the early accessories? im sure the smog station will notice my car is a 1993 and expect a smog pump on it..

Do they have a book or something with pictures of every model year with each motor? I pass visual fine here.

My '88 750iL has no air pump, yet my '88 F150 did.

Just use the '89 and earlier M103 parts. Alt bracket, fan bearing bracket, belt, etc.

__________________
I'm not a doctor, but I'll have a look.

'85 300SD 245k
'87 300SDL 251k
'90 300SEL 326k

Six others from BMW, GM, and Ford.

Liberty will not descend to a people; a people must raise themselves to liberty.[/IMG]

there actually is a gigantic book at one smog place ive been to and it lists all the characteristics of the current car you're looking at. tells you all the info about the engine such as displacement, cylinders, injection type, and i remember seeing a field with smog pump as Y or N option. maybe my brain is making this up. *shrug*

i do remember though the guy was specifically looking at my smog pump each time i had the car tested.