300 E Died on Highway
 

My 91 300E died on the highyway this afternoon, had it towed to the closest MB dealership. They can not look at it for a couple days, so I was hoping I might get an idea of the problem before the service department calls... here's the details.

Coming off the on ramp (~40Km/hr) I dropped the auto trans into 3rd then floored it. the car accelerated as usual and I did my lane change. I shifted into D at about 5500 rpm. Almost imediatly I lost power. The engine did not rev when I stepped on the gas. As I was pulling over to the medium I lost power steering and power brakes. All the electrical consumers were operating fine as I pulled over and stopped. I let the car sit for a few minutes then tried to start it. The engine turns over but does not fire. A quick look under the hood showed no loose or disconnected wires, i.e. ignition coil, spark plugs, distributer, gas, ect. I have 1/2 a tank of gas in the car too, so I know thats not the cause :)

The irony of this is I was on my way to a trade expo with 2 collleagues and we took my Benz, it being the most reliable and comfortable of the other vehicles avalible. I guess we should have taken the Rabbit hatchback then I wouldn't be sitting here wondering what broke on my Benz. Any ideas guys?



Cheers for now
EADG

Been there.

I vote fuel pump or fuel pump relay.

Sneak into the dealership with a heavy blunt object (like the handle end of a big screwdriver, or your tire iron), crawl under the car, and give the fuel pump a firm whack.
If it starts, you need a fuel pump, otherwise suspect relay.

All of this presumes you have spark, but it just smells like fuel to me. Best of luck.

Yep sounds like possible fuel pump problem, You may be able to turn the key to the no. 2 position (when all lights on the row underneath speedo are lit) and listen for the pump if nothing it is probably the relay.. Good luck

forgot to mention there are 2 fuel pumps on your car also

A MB Service Advisor called me this morning with the diagnosis for my car. The distributer rotor broke. They are replacing the rotor, distrubuter cap and shwroud and some vacum lines that were damaged by the rotor. Total cost will be $480 CND with tax, that includes the 1 or 2 hour charge for diagnostics. $88/hr. I'll be back on the road tomorrow evening :)

Cheers for now
EADG

I have a hard time believing a Mercedes dealer (I though they were all specialists) would need 1 to 2 hours to diagnose a deffective cap/rotor. AI'd say that if a competent (?) mechanic could not find this problem within 20 to 25 minutes, he should be fired or returned to Mechanics 101.
JackD

No dealer will ever charge less than an hour for diagnostics. Probably took almost that long too -- there are many reasons a 300E will just die, and they have to be eliminated. A broken rotor wouldn't be my first guess, either!

Peter

Well, It's easy to say this now, but when i read the post I was thinking either fuel pump or rotor bracket broken. I've seen this a few times. It can be hard to diagnose because you actually can have a situation where you will have spark, the rotor will turn, but just not be firing at the correct time to run the engine. It
can be tricky.

Gilly

I've seen broken rotors before, and they usually baffle the tech for a while. Unless they blow apart completely, you get spark, although it can be erratic.

Even no spark isn't a sure bet for a busted rotor -- I'd personally check for a bad OVP relay myself!

My brother's Buick split a rotor once -- he was ready to change the timing chain when I suggested he check for spark first. Zip -- took the cap off and there were only bits for a rotor. Cheap fix, but took a bit to find....!

Peter

The previous post mentionned they had to replace the shroud and some vacuum hoses that were damaged by the ''exploding'' rotor/distributor cap. If this was the case, I would think it would have jumped to a trained eye while opening the hood. Happy to hear the problem was solved.
Dan, I'd like your opinion on a previous post I made concerning problems with the A/C and heater system. You,ll find it dated yesterday. Nobody here seems to have a possible cause.
Thanks
jackD

Jack:
I'll look for it.
I understand your comment now. Yes, if the damage was severe enough to actually break the cap, I'd go along with you that it reflects poorly on the tech, depending on severity and location of the damage.
The usual problem is called the rotor bracket, which is a metal piece that attaches to the front of the camshaft, but on the front of the front cylinder head cover. The rotor attaches to this bracket with 3 small machine screws. The bracket can crack radially, which means that the rotor tip won't neccesarily be pointing at the correct cylinder anymore inside the cap.

I picked up my car this evening, runs great. I misquoted in my last reply, the bill was $480 + tax, for an amount of $560 CND. I'm looking at my bill and I have a question. Says here they repaired (replaced) lines for EGR and Supply Vaccum. I looked under the hood when I parked the car and I saw the lines they replaced right away, thing is, I never remember having lines there as long as I've owned the car. My question is what are they for... what does the EGR do and what is the supply vaccum for? What happens when they are not connected?

Cheers for now
EADG

i would complain because all dealerships i have ever gone to, have always said that any diagnostic fees would go towards the total repair.

also how does a rotor damage vacuum lines? rotor spins inside the distributor cap...

sounds pretty fishy to me unless i just don't know what i'm talking about.

Actually, I was wrong again in last reply... the lines were not damaged by the rotor. It was a misunderstanding on my part during the telephone conversation with the service advisor. The 2 lines that were replaced were either damaged (i.e. old, cracked, cut, ect) or missing. And yes, the diagnostic charge was included in the total bill, here's the break down; Parts: $223, Labour $264, Tax $73


Cheers for now
EADG

yikes...
are you in the states?
or abroad?
if you're in the states i would suggest you getting your parts from partsshop here with Phil and then taking them to the mechanic

could save you so mush money