Engine Management Light issue

[ChrisA]

Fuel light appeared with 60 miles to go, pulled in to a Filling Station with 32 miles showing on the dash and filled up
35 miles down the road, engine management light came on. Rang Paul who talked me through storing the code so the light went off. 250 miles down the road, again..... filled up and 30 miles further, EML on again. This time couldn't clear it
Got back to UK and went straight to EC UK and on to STAR. Error code P201D-004 appeared. Baffled Paul and Andy so cleared code and off I go again. 38 miles and EML back again!! I've managed to store the code twice before but now the light stays on.

Any ideas? Maybe fuel cap pressure, canister purge valve or shut off valve?

I try to always fill up with min 98ron but had no choice but to fill with 95ron so could this be an issue? 6 tanks full of 100 or 102ron and then 95ron, maybe engine got a little confused?

Any clue guys?

 

[whitenemesis]

Low RON shouldn't trigger anything as the anti-knock sensors will adjust timing to compensate.

Found this -

P201D-004 mixture formation unit adaptation,idle mixture too rich.[P0172]

which apparently is a failing MAF?

 

[ChrisA]

Low RON shouldn't trigger anything as the anti-knock sensors will adjust timing to compensate.

Found this -

P201D-004 mixture formation unit adaptation,idle mixture too rich.[P0172]

which apparently is a failing MAF?

Thanks mate,

I did say to the guys it was probably running too rich and needed to sort the remap out..............


I'll throw a bottle of Techron in and see if it helps

 

[whitenemesis]

Techron wont touch the MAF

 

[ChrisA]

Techron wont touch the MAF

I know, but we don't know it's the MAF
If it's a different issue, the £14 spent on the Techron is a lot cheaper than back on STAR so I was thinking give that a go first

 

[Lee C63]

I know, but we don't know it's the MAF
If it's a different issue, the £14 spent on the Techron is a lot cheaper than back on STAR so I was thinking give that a go first

I know its throwing good money after bad but if you have had the engine light on 3 times is it not worth getting it put on STAR again in case its something more sinister than a MAF.
Surly at some point your luck has to change and things run sweet for a while

 

[ChrisA]

STAR is the obvious choice Lee as you say but it's been on there twice now and none the wiser
Will be back at Paul's in the morning.....fingers crossed

Luck WTF is that

 

[BillyCR]

Techron wont touch the MAF

55 AMGs don't have a mafs as far as I am aware they run map, the code relates to running rich at idle due to adaption values, I suggest disconnecting the battery and leaving for a couple of hours, and reconnect and see how it goes. I would not put fuel additives in when running colder plugs as there is a good chance these will get ruined.

Problem is that code could mean anything, either way you don't want any car running rich for long periods of time, so its needs resolving.

If I had to have a guess I would say its the throttle body, and its only a guess.

 

[Alex]

I think he meant O2 sensors - 55Ks don't have MAF.

In my old car that was running rich under load, a retune has helped. Had to be driven to be properly diagnosed though.

 

[SavMan]

Just to add EML is on but in Star there are no codes or events in the ECU control unit. It was only when we checked in developer mode within the ECU control unit that we found the stored code that Chris has posted above hence why it's in German. Chris is coming in tomorrow so we can do some further testing.

 

[ChrisA]

I think he meant O2 sensors - 55Ks don't have MAF.

In my old car that was running rich under load, a retune has helped. Had to be driven to be properly diagnosed though.

O2 Sensors were changed last month.........
Alx, we discussed the remap so hopefully that will sort the issue out

 

[ChrisA]

The issue was the Piggyback connection for the injectors. Removed, cleaned and put back by Andy@ECUK
Running like a dream now