Oversized Asian Fuel Filters.

[Scdevon]

I have a confession. I've never changed the fuel filter in my '89 Corolla in 218k miles. The filter is huge. By eyeballing it, It has at least 10x the capacity of older screw-in, tiny sintered bronze fuel filters that used to screw into domestic carburetors and such which seemed like they were always good for at least 30k miles. I'm a former ASE Master Technician with Domestic (GM) experience and Toyota experience. While I was a line technician at a Toyota dealership, I can honestly say that I never saw a "clogged" fuel filter on a fuel injected Toyota because the things have huge capacity.
While I agree that it SHOULD have been changed by now, I view it as an experiment to see if a Toyota fuel filter is actually a LIFETIME fuel filter. I run MMO in the tank at every fill up. I also think that the new generation of in-ground gas tanks is much better at gas stations than they used to be. It's almost unheard of to get a "load of bad gas" anymore. Are there any other cheapskates like me running their original fuel filters to insane mileages?

 

[senquack]

Very interesting to hear this from a tech. I always thought the filter was awfully huge for the small amount of debris it would be seeing.

 

[Scdevon]

Originally Posted By: senquack
Very interesting to hear this from a tech. I always thought the filter was awfully huge for the small amount of debris it would be seeing.


The car's gas filter is really like the 3rd line of defense anyway. The gas is filtered at the gas station's pump. The gas is filtered at the in-tank "sock" at the intake of the electric fuel pump in the car's gas tank. If anything DOES get past the car's fuel filter, there are tiny mesh filters on each fuel injector as a final line of defense.
Im not surprised that the replaceable in-line gas filters see little to no debris. Since I run MMO in the tank, I'm sure that there's zero rust in there, too. Another reason to run lube in your fuel.

 

[Chris Meutsch]

I have never changed my in-tank filter on my 2001 Civic @ 200,650 miles. I've thought about it but it ain't broke so I'm not going to fix it. I run a bottle of Techron through it every 20k.

 

[Chris142]

I've changed plenty of plugged up fuel filters on the 4cyl Toyota trucks. They put the filter below the intake manifold and above the starter which is a terrible place unless you have an extra set of wrists.

 

[Scdevon]

Originally Posted By: Chris142
I've changed plenty of plugged up fuel filters on the 4cyl Toyota trucks. They put the filter below the intake manifold and above the starter which is a terrible place unless you have an extra set of wrists.


I know first hand that they're a PITA to change, but I've never seen a "plugged up" one. At what kind of mileage were you seeing them restricted?

 

[Chris142]

I don't remember the milage. I do remember that I couldn't blow through them and the trucks were much peppier with the new filter.

 

[2oldtommy]

Scdevon, Remember too, that rust from the fuel tank is a thing of the past if you have a late model with a PLASTIC fuel tank. I have never changed a filter on a car until 100K miles or more.FWIW-- Oldtommy

 

[Scdevon]

Right, but fuel lines are still made of steel or aluminum. Lots of room for corrosion still. I like to think that MMO or other lubricant added to fuel reduces or eliminates this. Plastic fuel tanks were a huge improvement, though.

 

[mechtech2]

Gas filters for modern fuel injected cars are large.
They have a lot of surface area inside.
This equates to a long service life.
If your fuel is good, they can last a REALLY long time, as you experienced.

Filters at the gas pump are very good.
The fuel pump pick up filter is only adequate for birds and small rodents.
The in line filter is excellent, to keep the insanely machined fuel injectors clean.

 

[ET16]

The filters may not have been clogged, but I often feel slightly better acceleration in my cars after changing a fuel filter. I've always thought that the flow was slightly improved by the new filter.

 

[Silk]

When changing a fuel filter I give it a few smacks on the bench top,then drain it into a container to show the customer.The drained fuel is always black,from the fuel pump brushes.Doesn't restrict flow to any great extent,but sure looks good for the customer.Preventive maintenance,you do it or you don't.If it's in the service schedule it's either done or not....or you tick the box without doing it.

 

[nthach]

Open up a OEM Denso or a Nippon brand from WorldPac for a Toyota app, and it's a crazy design - it's depth media with SEVERAL layers of fine filter paper - think the stuff used in laboratories wound around a resin core. Most everyone else is still using pleated media.

 

[Scdevon]

I believe the OEM filter on my 'Yota is a Denso. I've seen them cut open and I can tell you that they're of VERY good quality. The engine pulls great while rowing through the gears even at wide open throttle. I'm not convinced that the fuel filter is restricted at all even after 20 years.

 

[andyd]

Silk, thankyou for explaining what the black crud was. I got 100k miles out of a fuel filter for my 528e. I basicly changed it because it had been in there so long. The new filter made the car a bit peppier, so it was time to replace it.