This is why you should change your Fuel Filter
- Thread starter z287mgte
- Start date
IwantMKIII;1610610 said:
All of the fuel in the tank has been through the filter numerous times, its a return system and if your injectors saw that kind of fuel, well... i believe they would be junk. I just think its hard to believe that a filter can pollute a system like that. I think you are confused about the direction of flow and have a rotting tank. Its something to check, at-least.
whitemike;1610612 said:
The article you read was about the superior quality of Toyota filters, not after-market replacements.
Its not that difficult to figure out which end goes to the tank.... in the instructions it even tells you to take of the post filter end off first. Also after the filter was removed i just let it hang. There is a lot of fuel in both of the containers for it not to be unhooked the right way. Believe me or not doesn't matter. IndyMK3 was also there to validate my story.
mkiiichip;1610623 said:
As I mentioned previously, I have had the SAME results on several different vehicles including 3 supras and a camry, all with the "lifetime" filters. Honestly, the camry was the worst, it was darker and dirtier than the OP's by far. The filters may last a lifetime, but its still a FILTER, which mean dirt will accumulate over time and A) needs to be replaced or B)needs to be cleaned (which I have done before by simply reversing the flow with some pressurized water with excellent results).
And that has nothing to do with the fuel returning to the tank and getting clean until it goes through the filter again.
A filter will not make the fuel coming out of it any dirtier than it was going into it. It doesn't matter if it's a new filter or an old one, if the particles are too small for the filter to catch they will pass through anyway (and if they are that small they will also pass right through the fuel injectors). If the particles are large enough for the filter to catch, they will stay there forever, they won't eventually just go through anyway (unless they corrode and break up into a size that's small enough that they can pass through the filter and injectors). The only time the fuel filter will contaminate the system is if it fails from pressure buildup or corrosion (I've never seen it happen).
It's just a good idea to change it if you're having fuel starvation problems or changing the fuel pump. A clogged filter can kill a fuel pump, it causes the pressure before the filter to build up and makes the pump work harder. I've seen the fuel filters in some cars clog to the point that the 70psi bypass valve in the pump had to open. Some cars don't have a bypass valve and the pump just stalls around 70-100psi. Not good. Most fuel pumps with warranties require you have a fuel filter installed with the pump or the warranty is void.
It's just a good idea to change it if you're having fuel starvation problems or changing the fuel pump. A clogged filter can kill a fuel pump, it causes the pressure before the filter to build up and makes the pump work harder. I've seen the fuel filters in some cars clog to the point that the 70psi bypass valve in the pump had to open. Some cars don't have a bypass valve and the pump just stalls around 70-100psi. Not good. Most fuel pumps with warranties require you have a fuel filter installed with the pump or the warranty is void.
How about the OP cut open the old fuel filter and see what was in it, if it's not in the trash...
guys, i mean once its out of course ou can tell its oem, but what about those ppl ten years ago that didnt know the filter is a superfilter lol, and replaced it with generic parts store crap, those of course WILL mess up eventually, so theres no guarantee your car has oe toyota, check that cus my 87 i just sold didnt when i changed it, thus why i changed it, im not sure about my 89 so i shall check when it comes back, just sayin
we dropped my tank 3 years ago when I was doing the engine swap, and the tank was pretty nasty inside.. it wasn't horrible, but it was enough for us to clean it out without wasting the new gas that was in there.
I don't recall changing the filter for some reason.
I don't recall changing the filter for some reason.
destrux;1610995 said:
"Think outside the filter". You really think just because its going through the filter there is no possible chance it could come out worse then when it went it? Don't be ridiculous. These filters are meant for flow, which means getting out the big particles while the little ones pass, ones small enough not to hurt the injectors, but still enough to contaminate the fuel (maybe not negatively in relation to performance, but contaminate none the less), hence OP's issue, going in "clean" and coming out not so clean because it has to pass though 5 or 10 or more years of larger particle crap it already filtered out! I've seen the same result many many times, a quick flush of the filter resolves the issue unless your filter is just plain FUBAR (temporarily of course). Consider this, a filter similar to this one is used on water, a large chunk of salt is captured in the filter, yes the salt gets trapped but that doesn't mean it doesn't break down and dissolve into the water over time.
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Many modern cars don't even run fuel filters. Anything large enough to do damage is caught by the sock on the end of the fuel pump.
Just food for thought.
Just food for thought.
Never heard of a fuel pump sock that repels water. I've gotta see this.
But on topic.
Toyota filters are good but not infallible. I had fuel filter problems on a 95 Celica ST at ~160k. It had a slight stumble that had developed at idle and WOT.
Changed the plugs, rotor button, and the rotor cap and it was still doing it. So I took it to the local dealer to check valve clearances and timing. It came out exactly like it went in so I asked them if the fuel filter could be clogged and they gave the same response most people do about Toyota filters being designed to last forever.
After a few days of tossing things around in my head I decided to change the filter anyways.
Upon starting it up it was smooth as butter again. Ran like a swiss watch all the way up to 215k when I had the accident.
Ran into roughly the same problems with the Supra at ~140k. Can't say the 7M ever ran like clockwork but it did develop a bit of extra stumbling that was cured by a fuel filter.
Seems like most stories I hear about Toyota filters happen at 140-160k. While not forever it's much better than the ~30k average for aftermarket filters and well worth the extra couple bucks (you more than make your money back not buying more filters).
But on topic.
Toyota filters are good but not infallible. I had fuel filter problems on a 95 Celica ST at ~160k. It had a slight stumble that had developed at idle and WOT.
Changed the plugs, rotor button, and the rotor cap and it was still doing it. So I took it to the local dealer to check valve clearances and timing. It came out exactly like it went in so I asked them if the fuel filter could be clogged and they gave the same response most people do about Toyota filters being designed to last forever.
After a few days of tossing things around in my head I decided to change the filter anyways.
Upon starting it up it was smooth as butter again. Ran like a swiss watch all the way up to 215k when I had the accident.
Ran into roughly the same problems with the Supra at ~140k. Can't say the 7M ever ran like clockwork but it did develop a bit of extra stumbling that was cured by a fuel filter.
Seems like most stories I hear about Toyota filters happen at 140-160k. While not forever it's much better than the ~30k average for aftermarket filters and well worth the extra couple bucks (you more than make your money back not buying more filters).