C200K - Fuel Filter problem - help please!!

[rich1975]

We have just replaced the fuel filter on a C200k petrol (53 plate) - all seemed to be ok but after filling up with fuel today the car would not kick down and the engine power is dramatically restricted (it also wont let you rev it above 4000 rpm)- finally the engine warning light has come on and the car appears to have gone into "limp home" mode.

We cant have a look today as it is dark now but I am thinking we must have got the hoses mixed up somehow when we put the new filter in. There were four connectors in total. I am sure we got the arrow the right way round - does anyone know why there are four hoses going into the filter and does this sound like the problem?

Any advice appreciated - thanks

 

[roofless]

you can check with this http://www.detali.ru/cat/oem_mb2.as...605716.628&CT=F&cat=66U&SID=47&SGR=035&SGN=02

 

[television]

If the light has come on, then it looks like fuel contamination of the O2 sensor, maybe someone else has other ideas

 

[rich1975]

Thanks for this - I will check this first thing in the morning.

We definately got the arrow on the filter right (i.e. facing the outside of the car) - if we got the hoses mixed up would it cause the symptoms described and could it have done any damage?

Regards

 

[rich1975]

If the light has come on, then it looks like fuel contamination of the O2 sensor, maybe someone else has other ideas

How would we remedy fuel contamination of the 02 sensor?

One other point is that one of the injectors has started ticking for about 5-10mins and then it disappears? Could this also be contamination?

Thanks

 

[rich1975]

Just a thought - should we have filled the filter with fuel first or could there be air in the system? Is there a way to bleed it?

 

[television]

No they are self bleeding, and this would not put the engine lamp on

 

[roofless]

it might be a fault due to oil from the cam magnet getting in to the loom not one i know a lot about but someone will put you right

 

[MB TECH WARRINGTON]

it might be a fault due to oil from the cam magnet getting in to the loom not one i know a lot about but someone will put you right

could be but could be million and one things with these.
it may not even be related to fitting of fuel filter or fuel, get fault code read then repost ill try give you some pointers

 

[roofless]

could be but could be million and one things with these.
it may not even be related to fitting of fuel filter or fuel, get fault code read then repost ill try give you some pointers

is it not worth checking the maff for traces of oil as this would give a indication of a fault with oil in the loom or not

 

[television]

is it not worth checking the maff for traces of oil as this would give a indication of a fault with oil in the loom or not

yes, just wipe your finger over the top, that would answer that

 

[MB TECH WARRINGTON]

is it not worth checking the maff for traces of oil as this would give a indication of a fault with oil in the loom or not

no, oil will stay in the loom if the magnet is leaking, it may get to the electrical plugs of the components, usually if there is oil in the intake system this can indicate blocked breathers etc underneath inlet manifold. this can put the light on and often shows as secondary air injection faults

this is how i understand it to be, i may be wrong though,

 

[rich1975]

could be but could be million and one things with these.
it may not even be related to fitting of fuel filter or fuel, get fault code read then repost ill try give you some pointers

Thanks for the suggestions -

It just seems like too much of a coincidence that the fault has occured at the same time as us replacing the fuel filter.

You mention that it could be oil contamination of the loom. What do you mean by this? Where exactly am I looking for the oil? I took the plastic cover off the engine and there was some minor traces of oil around the filler cap.

I am really hoping that it is related to the fuel filter now!!

 

[roofless]

no the oil can leak from the cam magnet into the loom that runs from it 68 on this link http://www.detali.ru/cat/oem_mb2.as...627716.630&CT=M&cat=68Z&SID=05&SGR=030&SGN=01

 

[MB TECH WARRINGTON]

Thanks for the suggestions -

It just seems like too much of a coincidence that the fault has occured at the same time as us replacing the fuel filter.

You mention that it could be oil contamination of the loom. What do you mean by this? Where exactly am I looking for the oil? I took the plastic cover off the engine and there was some minor traces of oil around the filler cap.

I am really hoping that it is related to the fuel filter now!!

on the front of your engine, under a small plastic cover, usually with the tri star on, there is a small brass coloured discs, with 3 allen key bolts, bolted onto the front of engine on the right, with a brown coloured plug sticking out, remove this plug to see if its got oil inside. if it has get to a recommended indie or dealer to see if its got to other components inc ecu.

 

[rich1975]

Checked the fuel filter today and we had installed it correctly. Also checked the cam magnets and there is no oil leaking whatsoever - there is also no traces of any oil in the wiring loom or the ECU or any of the connectors (thankfully!!)

Took the car out for a longish run and the power was about a third of what it should be but the engine warning light did not come on. It was not misfiring but when you put your foot flat to the floor out of a junction it would bearly set off until eventually the revs very slowly increased. It seemed like it was definately fuel starvation. It also would not kick down at all.

We then pulled over switched off the engine and restarted the car. Low and behold the power was back as normal but this has resulted in the engine check light coming on again. However this time it did not go into "limp" mode.

Got back home and took the negative off the battery for about an hour. Now it is running back at full power and the warning light has stayed off. Been out about another 3-4 times and again all is well thankfully.

Could it have been air/contamination in the fuel line which has suddenly cleared itself? Its running like a dream now.

Thanks for all your help on this - I now know lots more about the car!!

 

[roofless]

Checked the fuel filter today and we had installed it correctly. Also checked the cam magnets and there is no oil leaking whatsoever - there is also no traces of any oil in the wiring loom or the ECU or any of the connectors (thankfully!!)

Took the car out for a longish run and the power was about a third of what it should be but the engine warning light did not come on. It was not misfiring but when you put your foot flat to the floor out of a junction it would bearly set off until eventually the revs very slowly increased. It seemed like it was definately fuel starvation. It also would not kick down at all.

We then pulled over switched off the engine and restarted the car. Low and behold the power was back as normal but this has resulted in the engine check light coming on again. However this time it did not go into "limp" mode.

Got back home and took the negative off the battery for about an hour. Now it is running back at full power and the warning light has stayed off. Been out about another 3-4 times and again all is well thankfully.

Could it have been air/contamination in the fuel line which has suddenly cleared itself? Its running like a dream now.

Thanks for all your help on this - I now know lots more about the car!!

that's a good ending we hope but it might help to have the code read to put your mind at rest just incase it returns

 

[rich1975]

I agree. Is there an easy way to get the code without spending ££££. No doubt MB will want £70 to plug in and read the code.

Can you buy a fault code reader which could be cost effective and come in handy in the future?

 

[roofless]

you might have a independent mercedes specialist in your area & if they do it will be more reliable due to knowledge of the brand & cheaper

 

[television]

At this stage why not unplug the MAF and try the car without it plugged in, this would also fit the bill on your fault as its key clearing