300 ce 24v starts/stops

danandgerry

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Having trouble with the old girl,she starts runs for a while then stops leave her for an hour or two starts agian after a while stops agian,my mech is baffled
 

brigadier

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You need to gather more info. First of all check for spark when it stops. Could be bad coil, ignition ecu, ovp, fuel pump or relay.
 

grober

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As been said fuel or ignition--- usually means something is getting " stressed" after running for a while and overheating. Could be the MAS RELAY [ the larger fuel pump relay fitted to 300-24v cars] or possibly more likely the EZL ignition unit on the wing- the heatsink compound between it and the wing dries out leading to overheating and eventual failure. you could try renewing the heatsink compound and see if things improve but usually by the time faults are apparent its too late. Other thing to try as a test is to give it a blast with "freezer spray" when it happens to see if it restores function
 

mattc

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Crank position sensor on way out?
 

grober

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Its pretty basic really. If a car starts and runs OK then really there's only 2 things stop it. Loss of spark or fuel. Your mechanic need to determine which. Usually fuel starvation takes slightly longer to develop than ignition failure but it takes experience to determine which is which especially if it happens when the car is driving along the road. Two tests would be to put a pressure gauge on the fuel line to monitor fuel pressure when the failure occurs and to run the car hooked up to an old oscilloscope engine analyser till it fails to monitor the cylinder firing lines. I wonder if your mechanic is a little out of his depth on this one? One outside possibility is fuel starvation due to a build up fuel tank vacuum - easily tested by running with the petrol cap slack.
 

RBYCC

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My question would be that when it stops does it do so immediately as if you've turned the key off or does it sputter and slowly die ?

To follow up on Graeme's post....

Immediate would indicate ignition, slowly would be more likely fuel.

Could be something as basic as the ignition switch or secondary ignition circuit wiring...or the fuel pressure regulator as the CIS-E needs to maintain a controlled pressure to function.

One thing that you can do yourself is to remove and read the spark plugs which seems to be a forgotten method of engine diagnosis.

Color of plug, or if wet with fuel or oil tells volumes..:thumb:
 
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ray_hennig

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Having trouble with the old girl,she starts runs for a while then stops leave her for an hour or two starts agian after a while stops agian,my mech is baffled
If I was allowed one guess, with those symptoms, I would say distributor rotor arm.

That's what it was when mine did that.

RayH
 
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danandgerry

danandgerry

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Thanks everyone, theres a spark theres fuel sometimes she starts goes for awhile then just stops.Originally called out the AA he said I think its that, pointing at the thing to the right of the distributor,the next day the recovery man came I said shall I try it and it started drove it on to the truck because it didn't sound right ( the AA man hadn't put the plastic cover on the front of the engine correctly) 20 minutes later wouldn't start agian. Mech now looking loom.
 

carat 3.6

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Thanks everyone, theres a spark theres fuel sometimes she starts goes for awhile then just stops.Originally called out the AA he said I think its that, pointing at the thing to the right of the distributor,the next day the recovery man came I said shall I try it and it started drove it on to the truck because it didn't sound right ( the AA man hadn't put the plastic cover on the front of the engine correctly) 20 minutes later wouldn't start agian. Mech now looking loom.
It wont be the loom at fault, I would advise that you find a mechanic that can diagnose the fault properly.

In my opinion it wont be a fuel related fault, but an ignition problem causing a loss of spark. The syptoms also point to the fault being heat related, as the car will start again once it has cooled down.

Possible suspects are: EZL ignition module, MAS relay, OVP relay, Crank sensor, rotor arm, distributor cap, Ignition coil.

Your mechanic probably dosen't know how to use it, but there is a basic fault code system built into these cars. You will need a flash code reader to use it.
 

brigadier

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As grober suggested you could use freezer spray on ezl unit and coil too see if that changes things.
 

ray_hennig

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As someone else said, "Heat related".

My rotor arm was breaking down when hot. It's a cheap fix (well, maybe €50) and if it hasn't been changed for ages, give it a try.

And don't start worrying about costly items like EZL until you've addressed the basics. The HT on these engines needs to be in 1st class order for things to work at their best.

RayH

PS: And don't be tempted by a cheap rotor arm. My 18 month old Bremi part was the one that broke down. I replaced it with the 17 year old original and that worked fine until I bought another original from Euromerc.
 
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brigadier

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Bosch or Beru are the choices when it comes to HT parts.
 

ray_hennig

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Bosch or Beru are the choices when it comes to HT parts.
My preference for HT components is:

1. MB but not for plugs.
2. Beru
3. Bosch

and then NGK for plugs and probably leads as well.

Bosch gets ranked under Beru for me because of difficulty in getting copper, non-resistor plugs.

Just my 2c worth.

RayH
 
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danandgerry

danandgerry

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Old girl Sorted, wiring to variable cam sensor renewed,mixture adjustment screw damaged tamper proof screws removed to enable repair, air filter and housing cleaned
fuel pump relay and main power relay checked some contacts were poor in main relay, fuel filter checked, coolant temp sensor not working within range renewed.It started ran smoothly for 5 mins then cut out then wouln't start,crank sensor thought likely renewed she starts and runs but misfires when hot,on close inspection corrosion and tracking in distributor cap this was replaced engine runs smoothly but emissions not exceptable,vacuum pipe from fuel pressure regulator found to be fitted incorrectly was attached to air filter housing should be connected to inlet manifold this sorted emission problem, ignition module removed new heat sink paste applied(thanks grober). sorted. Phew!!! finger hurts
 

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