C32 Consumption problems

[iainw]

Hi, Just sense checking here as i do need to get to work on this issue shortly.

My c32 has since i bought it produced woeful MPG numbers, its also kicking out a huge amount of head from the cats which combined with a sooty looking exhause leads me to conclude its running rich, very rich.

Driving like a granny sees about 20mpg booting it sees about 6mpg.

Looking at the lamdba volts on my phone shows that they are fluctuating and do hit some of the higher numbers cir .9v iirc.

No fualt lights or codes are lit (apart from my srs one).

I am presuming that the lambda's are the fault given the age of the car and its consumption.

Any thoughts?

The dash is showing a normal coolant temp so i am presuming this sensor is good, but does the ecu have its own sender?

Will the ecu on these engines take a universal bosch or walker lambda without throwing its toys from the pram?

many thanks in advance.

 

[Dizwen]

pottering around 17-21 mpg.

On a steady motorway run I got 30.2 mpg.

And that was before my power loss problem.

 

[iainw]

pottering around 17-21 mpg.

On a steady motorway run I got 30.2 mpg.

And that was before my power loss problem.

Yep, sounds about right, mine is over fueling badly, so the only causes i can think of are, the lambda's are goosed or the engine thinks its in warm up all the time as the ecu has a separate temp sensor.

It would be handy if anyone could assist on these points before i buy a load of lambda's

 

[Stratman]

Take it to a good independent MB specialist and have it put on the STAR computer. That will show where the problems are.

 

[iainw]

Take it to a good independent MB specialist and have it put on the STAR computer. That will show where the problems are.

I have pulled any codes with a snap on solus but the only code present is the SRS.

As i am on the IOM, the only alternative would be Merc main dealer, and they are ******g useless.

 

[tjs_riley]

"the engine thinks its in warm up all the time as the ecu has a separate temp sensor."

Any idea where this temp sensor is ?
I'm having a similar problem. A 3rd party OBD2 reader and software show that I'm in open loop all the time and never go into closed loop.

 

[vijilants]

Id probably say that you are far beter off putting it on a STAR. Ive seen how the STAR works when it comes to checking out the lambda as I had it checked on my car using a STAR and it dynamically checks the output of the lambda.

ODB code readers are unable to perform this function.

Any half decent indie specialising in Mercs will have a STAR so you are not limited to the dealership.

You could also go back to the old school method and pop a spark plug out to see what colour it is showing at the electrode just to confirm your thoughts on running rich