W124 300E stalls at low revs

[bicyclerm]

Hi

Our lovely 300E, which we bought new in 1990, and has only done about 60k miles, has an annoying problem whereby it cuts out at low revs. It'll start again immediately. Our garage has run out of ideas. It's been a recurring problem over the past few years but now is so bad that it's dangerous.

To try to fix this, and an issue with poor starting, we have recently had the fuel pumps, distributor cap, coil, voltage overload protector and injectors replaced. This has fixed the poor starting but the engine still cuts out at low revs.

Can anyone help me by suggesting any ways to diagnose what's at fault. I'd love to fix the car as it's a great motor but I can't justify running up large garage bills as it's not worth that much. If there's anything I can try myself then I'm keen to give it a go.

Thanks
-BRM

 

[carat 3.6]

Welcome to the forum.

When it cut's out, will it just die or dose it seem to struggle then stall?

When it dies, can you here the fuel pump running? (buzzing sound from near the rear wheels).

Have you had the fuel pump relay checked?

Where are you located?

 

[bicyclerm]

When it cuts out it just dies immediately. We haven't noticed the fuel pump but it's only seemed to cut out in situations when we need to get going in a hurry so we haven't really paid much attention. We've have new pumps but not sure about the relay(s).

If I take it on a test drive, is there anything else I should check for when it cuts out other than the sound of the fuel pumps?

-BRM

 

[carat 3.6]

How often dose it cut out, everytime you use it or randomly?

I suspect you have a dry joint in the fuel pump relay, causing the fuel pumps to cut out.

 

[bh13coupe]

My w124 coupe stalled occasionally, the tickover was fluctuating as if it was trying to compensate and catch the stall. The fix was to clean the throttlebodies. Mine were not sealing the air off at tickover so the ecu/maf was getting confused. It was an hours labour.

 

[mattc]

I borrowed a 300e once and whilst I had it the engine would cut out without sufficient revs. Turned out to be a split breather hose. Could be that simple I hope

 

[bicyclerm]

Thank you for all your useful replies. Very helpful. And plenty for me to get working on.

A bit more background info: it's been doing it for about a year and until recently would only cut out about once every couple of months. In the past weeks it's started to cut out significantly more often. The cutting out is random and not every time it's running at low revs.