Issues with my 1984 W123 280 CE

[Glasfryn]

Hi, can anyone help, I have an issue with my W123 280CE.

The car starts without any issue from cold (out of the garage) I drive for a few miles then I call to a petrol station, I switch the car off, add fuel, go into the garage and pay, I walk back to the car and get in, it’s in Park with the hand break on, I turn the key and it fires up for a split second then dies. Despite trying it over again it still won’t start. I wait approx 10 minutes, turn the key then it fires up and I’m away. As I drive a few miles then I reach a T junction or roundabout (when the car is idling) it will cut out then I have to wait a while before it will run again

does anyone else have or had the issue or does anyone know what the issue may be?

 

[SkegVegas]

When it stalls can you hear the fuel pump running.

 

[alabbasi]

Hard starting from warm is usually a sign of a failing fuel accumulator

 

[Glasfryn]

When it stalls can you hear the fuel pump running.

When it stalls can you hear the fuel pump running.

I can hear a very faint thudding

 

[Glasfryn]

Hard starting from warm is usually a sign of a failing fuel accumulator

Someone else mentioned that, is that the part that maintains the pressure in the pipe to prevent the fuel travelling back to the pump

 

[219]

Hard starting from warm is usually a sign of a failing fuel accumulator

As well as that , also think vacuum leak on the inlet manifold ; on the M110 , there is a breather pipe under the airbox that is known to crack and can cause a failure to run , and lots of little vacuum pipes that can come off , but usually just cause bad running rather than failure to start . These don't usually fix themselves . Also where the ignition leads run from the distributor over the cam bank they can ground out and short out your spark , but again will normally only kill individual cylinders - unless the 'king lead' between the coil and the distributor shorts out - watch the engine running in the dark and look for blue flashes to ground . Could just remotely be a bad ignition coil - unlikely though . Other issues I've had down the years are spark plugs that get fouled up and give exactly the symptoms you describe - pull your plugs and see what condition they're in . Could also be a hairline crack in the distributor cap which opens up when it gets warm in the engine bay .

It will be something simple .

 

[Bellow]

Someone else mentioned that, is that the part that maintains the pressure in the pipe to prevent the fuel travelling back to the pump

It prevents hot fuel in pipes vapourising and causing air locks.
Next time you have the issue, try cooling the fuel pipes in the engine bay (cold wet rag will do) especially at the highest points.

 

[alabbasi]

Someone else mentioned that, is that the part that maintains the pressure in the pipe to prevent the fuel travelling back to the pump

Pretty much, when your engine is warm, it does not rely on the cold start injector to run which is why you find it hard to start.

The accumulator is located right where the fuel pump and filter is as part of that assembly.

 

[SkegVegas]

When it won’t restart is there a smell of fuel. It could be on full enrichment like on a cold start. If this is the case the engine will flood wetting the spark plugs. Next time it happens remove a spark plug to check if it is wet. as it is a continuous injection system you have to wait or pull out the fuel pump relay and crank it over for a short while.

 

[219]

When it won’t restart is there a smell of fuel. It could be on full enrichment like on a cold start. If this is the case the engine will flood wetting the spark plugs. Next time it happens remove a spark plug to check if it is wet. as it is a continuous injection system you have to wait or pull out the fuel pump relay and crank it over for a short while.

A bit like pushing in the choke and keeping foot off the pedal n a carb car

 

[SkegVegas]

The enrichment is controlled by resistance to the metering head moving. There is a pipe on top of the metering head that goes to a valve bolted to the engine. This has a bi metallic strip that adjusts the control pressure as the engine warms up it also has an electrical heater element. The lower the control pressure the more the plate moves allowing more fuel in to the engine.
it is possible to check the control pressure but you need a special gauge.

 

[Bellow]

When it won’t restart is there a smell of fuel. It could be on full enrichment like on a cold start. If this is the case the engine will flood wetting the spark plugs. Next time it happens remove a spark plug to check if it is wet. as it is a continuous injection system you have to wait or pull out the fuel pump relay and crank it over for a short while.

If the fuel enrichment was permanently enabled - wouldn't it run rough as hell when warm at all times?

(Accumulator is the most likely culprit and even if not, needs checking if only to eliminate it as the cause).

 

[SkegVegas]

If the fuel enrichment was permanently enabled - wouldn't it run rough as hell when warm at all times?

(Accumulator is the most likely culprit and even if not, needs checking if only to eliminate it as the cause).

The accumulator retains fuel pressure in the metering head so the car has pressurised fuel to start as the engine is cranked. If it failed it would delay the engine starting as the fuel pressure would have to increase to allow the injectors to open by a few seconds but not stop it from starting. The car fires initially and the dies on a warm start. Once the car has faulted it needs to be checked for a spark at the plugs and see if there is fuel pressure or the engine has rich cut and flooded

 

[Glasfryn]

As well as that , also think vacuum leak on the inlet manifold ; on the M110 , there is a breather pipe under the airbox that is known to crack and can cause a failure to run , and lots of little vacuum pipes that can come off , but usually just cause bad running rather than failure to start . These don't usually fix themselves . Also where the ignition leads run from the distributor over the cam bank they can ground out and short out your spark , but again will normally only kill individual cylinders - unless the 'king lead' between the coil and the distributor shorts out - watch the engine running in the dark and look for blue flashes to ground . Could just remotely be a bad ignition coil - unlikely though . Other issues I've had down the years are spark plugs that get fouled up and give exactly the symptoms you describe - pull your plugs and see what condition they're in . Could also be a hairline crack in the distributor cap which opens up when it gets warm in the engine bay .

It will be something simple .

Thanks for you reply, it’s odd that it runs ok from cold but when the engine is warm the problems begin

 

[Glasfryn]

The accumulator retains fuel pressure in the metering head so the car has pressurised fuel to start as the engine is cranked. If it failed it would delay the engine starting as the fuel pressure would have to increase to allow the injectors to open by a few seconds but not stop it from starting. The car fires initially and the dies on a warm start. Once the car has faulted it needs to be checked for a spark at the plugs and see if there is fuel pressure or the engine has rich cut and flooded

Funnily enough I was on my way for the MOT, The car started from Cold, I drove approx 4 miles, called into a garage and added £20 fuel, paid the cashier, went back to the car and it failed to start, I gave up & phoned the MOT guy, when he arrived after approx 10 minutes the car started without any need to open the bonnet.
The mechanic later said that during the MOT he turned the ignition on for a few second, pumped the pedal and it fired up.
He mentioned that the fuel could be vaporised at the injectors and it needed the pump to send the liquid fuel for it to fire...... Any suggestion?

 

[Glasfryn]

Pretty much, when your engine is warm, it does not rely on the cold start injector to run which is why you find it hard to start.

The accumulator is located right where the fuel pump and filter is as part of that assembly.

Have you any knowledge where I can buy an accumulator and filter from?

 

[Glasfryn]

When it stalls can you hear the fuel pump running.

When it won’t restart is there a smell of fuel. It could be on full enrichment like on a cold start. If this is the case the engine will flood wetting the spark plugs. Next time it happens remove a spark plug to check if it is wet. as it is a continuous injection system you have to wait or pull out the fuel pump relay and crank it over for a short while.

i’ve not noticed a smell of fuel

 

[alabbasi]

Have you any knowledge where I can buy an accumulator and filter from?

I live in the states so my sources will be different to yours. When I lived in the UK (2 decades ago), German & Swedish and Euro Car Parts were the places to get German car parts. Crawl under the car and get the part #. There are a couple of versions so it's not safe to assume that any will fit.

 

[Glasfryn]

I live in the states so my sources will be different to yours. When I lived in the UK (2 decades ago), German & Swedish and Euro Car Parts were the places to get German car parts. Crawl under the car and get the part #. There are a couple of versions so it's not safe to assume that any will fit.

Good advice thanks

 

[grober]

FUEL PUMP PACKAGE MERCEDES 280 CE USA (123053)

Parts for unit FUEL PUMP PACKAGE MERCEDES 280 CE USA (123053)

www.ilcats.ru