Engine Fault Indicator is lit

Miffy

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Hi, today my Engine Check lit up and the car started to drive quite lumpy. I connected my OBD II reader and it showed Cylinder 1 Misfire.

After clearing the errors, I restarted and monitored the real time values
before the error
Fuel Sys1 = CL
Fuel Sys2 = CL

after the error
Fuel Sys1 = OL Fault
Fuel Sys2 = OL Fault

I disconnected the MAF (but a faulty MAF wont affect 1 cylinder?) The scanner confirmed the new errors of the MAF showing a low air volume, and the Rad FAN went on Permenent.

I have cleared the errors many times, and left it with the battery disconnected but the faults show within a min of starting the engine, and its clear its running lumpy.

A few other points need looking at also, the ODB reports engine temps of 82c but the guage in the car shows less than 70c . The MAF was reporting 4.89 g/s is this the correct value?
 

television

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Is the spark good Mark, though it does sound like an injector sticking
 
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Miffy

Miffy

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well, I havnt looked at the plugs, as they are only 6 weeks old, and i thought that if a coil pack was faulty then i would be getting 2 cylinders show a fault, but its only showing cylinder 1. is there a way to check the injector? Other than swapping it with number 2. are these easy to get at and change

btw, cars on just 63k now
 
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Miffy

Miffy

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Also, just to confirm, apart from the fan running even when cold with the MAF disconnected, it runs a lot worse so I assume the MAF is doing what its supposed to do. whats the reason for the fan to engage, I have not seen that mentioned anywhere
 

television

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If the electric fan (rad) is running all the time with the engine on (and not off) this shows normally that water has got into the fan control box, or the water or damp under the front SAM often accompanied with the washer level low on the dash
 
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Miffy

Miffy

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No, I meant the fan stays on if i disconnect the maf, with the maf connected I hardly ever notice the fan on
 

television

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Without looking at the diagrams I cannot comment, OK the MAS relays back info and air temp, so there could be some connection
 
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Miffy

Miffy

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ok, so maybe that makes some sence, any ideas on how i go about swapping the injectors? I had fords for years with injection but have never had any cause to look any deeper than changing plugs
 

television

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I can in the morning, though others could give you better advice
 
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Miffy

Miffy

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Well I think i have the answer, unless I have the cylinderr numbers wrong

I swapped over the coil packs from the front two cylinders and the fault has moved to number 4.

So I assume the numbering order is as below

SCREEN
3 6
2 5
1 4
FRONT
 

M.B.S.

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Hi. you said you replaced the plugs about 6 weeks ago was that for the missfire problem or was the car running fine before that, also if you dont use the correct tool for removing the plug leads they are easily damaged
 
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Miffy

Miffy

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plugs were changed as part of a service but as the fault has moved with the coil pack I am fairly happy the issue is there. just to see wheres the best place to get them now, else its down to the local MB dealer
 

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Euro and GSF sell them, I do not know the price difference
 
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Miffy

Miffy

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i just looked at euromerc (your signature link) and couldnt find any coil packs, i did a site search also

Is it normally acceptable to replace just the one pack ?
 

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Euro car parts they are on the net
 
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Miffy

Miffy

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thanks malcom, just checked, gsf dont stock them at all, and euro do not have any stock in, looks like main dealer
 


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