Deterioriating 190e Fuel Consumption & dodgy starting

[alanbp]

Hi

My ever reliable 190 has been showing worse fuel consumption over the last month or so. Ironically I have moved out to a country cottage and am driving in on A roads at a steady 55-60 mph so my consumption should be better! I was getting c30-32 mpg before (calculated when I fill up) and its now down to 28-29. Also after starting from cold (usually OK) and then switching off once warmed up - its runs lumpily and lacks power. It sometimes does and sometimes not! I am wondering if it could be the temp sender or the lambda?

Any suggestions welcome!

I am also still getting random "all the warning lights" coming on form time to time and when I check the battery terminals (engine running)with the volt meter its showing only 12 volts so I assume the alternator is hit & miss also!

Many thanks

Alan

 

[Stevie A]

I have a 190E 2.6 with rough running recently once warmed up and occasional hard starting. I suspect the OVP relay is playing up, either that or a faulty sensor.

From what I've read before, the engine starts from cold without too much sensor info needed, (although I'm not 100% sure about this), then once warmed up the engine / Bosch system needs the info from the sensors, or in other words, the sensor info is more critical to smooth running, hence rougher running when warm.

Or is it possible that once warmed up the OVP relay joints expand or something like that causing these problems?

Also, I archived this from ages ago:
For 190e idle problems look at:

Coolant temperature sensor (4 pin at front of engine)
Fuel shutoff switch (on throttle linkage)
Throttle position sensor (Built into bottom of throttle body, 3 wires)
Idle Control Valve (Right side of engine as you look in, 2 pin plug, a clean sometimes helps but sometimes you've just gotta replace it)

The only other thing I can think of is the sensor in the air intake in below the throttle butterfly flap / air filter assembly needing replaced or cleaned.

Report back when you find out what is cause.