Fuel filters?

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noogieman

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I Loewe Old Skool AMG
What are the culprits when fuel filter goes bad?
I know the fuel filtration will decrease, but what else happens?

Does mpg go worse with a worn filthy fuel filter?

What is the replacement interval on these?

It's been mooore than 10 years when I had it replaced last time.
 
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What are the culprits when fuel filter goes bad?
I know the fuel filtration will decrease, but what else happens?

Does mpg go worse with a worn filthy fuel filter?

What is the replacement interval on these?

It's been mooore than 10 years when I had it replaced last time.

Definitely overdue then! Have a look in the service book, the intervals will be in there
 
Clogged fule filter will affect MPG.

It will more noticeable at higher engine RPM. General lack of power and peak RPM, or flat spots during acceleration.

On Diesel engines, a new filter is due every 4 years. On petrol engines, it was every 4 years, but recebnetly they have moved to a filter that is incorporated in the fuel pump housing inside the fuel tank and due replacement every 15 years (not sure about the mileage offhand).
 
I have noticed an increased fuel consumption.
My increased fuel consumption started last year.

When I drive my car, she runs beautiful, has all the power and sounds like a beast on full throttle!
The RPM needle is stable not fluctuating up n down.
I have no leaks in vacuum system.

I suspected it might be the fuel filter or both air filters?
 
Could a bad fuel filter cause any damage to injection-fuel system or the engine by letting grime pass through the worn filter?
 
Could a bad fuel filter cause any damage to injection-fuel system or the engine by letting grime pass through the worn filter?

Possibly, if left for far too long the internal could disintegrate, but the usual way they fail is simply by getting partially (and eventually fully) clogged.
 
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I think fuel filter has approx 35 to 40,000 miles of use since the last time it was replaced.
I have no issues with bad idle nor start ups, only issue is a bit of decreased mpg.
 
What are the culprits when fuel filter goes bad?
I know the fuel filtration will decrease, but what else happens?

Does mpg go worse with a worn filthy fuel filter?

What is the replacement interval on these?

It's been mooore than 10 years when I had it replaced last time.
The engine stops at 0100 on the M23 on a freezing night and you're not with the AA / RAC et al.
Ask me how I know!
 
The engine stops at 0100 on the M23 on a freezing night and you're not with the AA / RAC et al.
Ask me how I know!

I guess you had an extremely bad luck from a bad fuel filter?
 
I guess you had an extremely bad luck from a bad fuel filter?
Yep, bad maintenance on my part!
First job I do on any mew car nowadays.
 
Could a bad fuel filter cause any damage to injection-fuel system or the engine by letting grime pass through the worn filter?
A blocked fuel filter will just restrict fuel flow. This is certainly the case on old indirect injection diesel engines where the symptoms of a blocked fuel filter would be an inability to rev due to not enough fuel flow.

Not sure if the same would apply to common rail diesels with their high pressure pumps.
 
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A blocked fuel filter will just restrict fuel flow. This is certainly the case on old indirect injection diesel engines where the symptoms of a blocked fuel filter would be an inability to rev due to not enough fuel flow.

Not sure if the same would apply to common rail diesels with their high pressure pumps.

similar thing would happen to petrol cars restricting fuel flow
 
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If your MPG is decreasing I would be looking at the air filter as the cause.
 
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If your MPG is decreasing I would be looking at the air filter as the cause.

Had the air filters replaced 2½ years ago, haven't covered the mileage yet to have them replaced.
Will have them inspected on the next service in 2021.

MPG is a bit decreasing when I check the fuel gauge during drive.
I will deffinately have the fuel filter replaced as well on the next service.
 

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