ML engine starting issue

[flowrider]

For the last few weeks I have had issues starting my ML320cdi from cold. I wait for the pre-glow indicator to go out as usual before I turn the engine over but it takes about 10-15 seconds to start and then a huge puff of smoke leaves the exhaust. The rest of the day the ML will start with no problem. I have an ODBII that tells me I have 2 fault codes, P0670 and P2270 both for powertrain.

P0670 - GenericTypePowertrain - Computer and Auxiliary Outputs - ISO/SAE ControlledDescriptionGlow Plug Control Module Control Circuit/Open


P2270 - GenericTypePowertrain - Fuel and Air Metering and Auxiliary Emission Controls - ISO/SAE ControlledDescriptionO2 Sensor Signal Biased/Stuck Lean
LocationBank 1 Sensor 2

What do the above codes actually mean?

Thanks

 

[BlackC55]

You need a new glow plug control unit and an o2 sensor.

 

[t-dawg1]

http://pages.ebay.com/link/?nav=item.view&alt=web&id=151264893557

Cheap on eBay,this is the new modified one by Beru. I fitted one on mine 12 months ago after similar problems

 

[BlackC55]

I am sure they are £116 from MB with a two year warranty.

 

[Merc Owner 2B]

Fit genuine MB parts only

 

[t-dawg1]

I am sure they are £116 from MB with a two year warranty.

£135+ vat from dealer here

 

[flowrider]

Thanks for the replies.......is changing the control unit an easy job that a semi competant non-professional mechanic (like myself) could swap out. If so any idea where the control unit is located on my 2009 ML.

Thanks

 

[flowrider]

Forget the last post, I have found the unit and it looks an easy fix.

 

[flowrider]

My local MB dealer has a control unit in stock £109 inc VAT so I have reserved it, result.

 

[flowrider]

I have now replaced the control unit and all fault codes have been cleared. The unit price was £139 inc VAT, apparently the person I spoke to yesterday in the dealer got the price wrong or I misheard .

My remaining query is that the unit I removed is a different design to the new unit. The old unit was squarer and had an aluminium back (photo 1), the new unit is all plastic (photo 2).