Best time to replace fuel filter?

[Belgian951]

As you probably gleaned from reading my frequent 'help me please' topics, I'm currently in the (hopefully) final stages of getting my car ready for a new go at the MOT inspection. Last time, I failed mainly because of high CO emissions.

To remedy this, I'm doing and have done a replacement of the crossover pipe, exhaust manifold, new gaskets and crush rings for both, new O2 sensor, new engine oil, new air filter (giving me issues as you can read in my hood problem topic), new MAF, new fuel rail (leaky), new injector seals, and probably some stuff I've forgot.

One thing I haven't touched yet is the fuel filter. I believe the previous owner replaced it some time ago (got the old one in his parts bin) but I'm not sure how old it is.

I want to know what the best time is for me to replace the fuel filter. The thing is that the gas in the tank (3/4 full) is more than 1 year old now, and I added stabilizer to it. Fresh gas would probably help with my upcoming emissions test, but I'm thinking a fresh filter would also help.

Would it however be better to drive around with the old filter, and when I get new fresh gas, replace the fuel filter? Or should I replace the fuel filter before emptying the old gas? Or does it not matter anyway?

[Thom]

Since you seem committed to get your engine to run as cleanly as possible you might want to drive around to empty your fuel tank then have the injectors cleaned/tested, replace the fuel filter and clean the in-tank filter in the outlet pipe of the tank, which is accessible by unscrewing it off the tank after the tank was emptied.

[Belgian951]

Since you seem committed to get your engine to run as cleanly as possible you might want to drive around to empty your fuel tank then have the injectors cleaned/tested, replace the fuel filter and clean the in-tank filter in the outlet pipe of the tank, which is accessible by unscrewing it off the tank after the tank was emptied.

Thanks, will do!