Injection pressure regulator

[amevill]

I have a 190E 2.5-16v which will not start! This we believe is due to a fault at the fuel distributor. It could be the pressure regulator. The only way out, as I see it. is to try another. Or is there a way to check it out first?

Can anyone help?

Amevill,

 

[Richard.Wilson]

Before changing anything, I'd check the pressure you've got now.
You need to Tee into the system anwhere between the pump and the regulator. Conventionally the regulator is at the return end of the circuit. I'm not familiar with the system on you car, but most are pretty similar.
You need to consult your manual for the correct value as it can be anywhere from 0.6 to 6.0 Bar.
You mention a distributor, so it sounds like it's mechanical (KE-Jetronic ) system, pressure is up around 5.5Bar. But you may also need to check each injector feed separately by spinning the motor over.
These mechanical injectors do get blocked though, and can be cleaned by any Bosch-type specialist.
However, you can do a pretty good job yourself . I use a couple of meters of fuel hose with a tyre valve in the end, fill with white spirit, connect to injector, pressurise the pipe with an airline. Mechanical injectors will open at 4 Bar and you can see the pattern of the spray improve as it clears.
Richard
Electronic injectors need to be opened with a 12V supply, with a light bulb as a buffer. flicking the injector open and closed fast will gradually clear the wax deposits. Not sure if this is approved of by most people, but it is a pretty fair simulation of what a specialist does in the cleaning rig, except they sometimes use ultrasonics as well.
If in doubt get a specialist to clean them

 

[dieselman]

Top Tips Richard.