fuel injection fuel filters

[spider2081]

A friend purchased a 1980 FI Spider that had been sitting a number of years, 5 years ago. He has since driven it 17,000 miles. When he bought it we removed the fuel sender and and looked in the fuel tank. It look pretty clean. So we replaced all the fuel hoses, installed a filter before the pump and the filter after the pump. Remover the FI rail cleaned it and had the injectors cleaned. It ran fine until recently when it started to act like the engine was pulsing when driving highway speeds. He tried the usual with the electrics to no avail. I was surprised he had not changed the fuel filters since he started driving the car. So yesterday we changed them. I cut open the filter we had installed before the pump. About 1/2 ounce of rust particles were in the filter. Some flakes about 1/4 diameter. I was shocked when I cut open the filter after the pump. The filter was clogged with a rust colored sludge like material. The filter before the pump is only 100 micron so it offers no restriction to the fuel flow. I believe the sludge is what passed through the first filter and was stopped by the second filter. I change my filters every year. When I looked in my owners manual I could not find a recommended schedule for the fuel filter. Also I think adding the filter before the pump saved his pump. For what its worth I had emailed Wix with the Fiats specs and they suggested using Wix filter 533248 Napa 3248 before the pump. Fiat had not used a filter before the pump.

[RRoller123]

That is most curious. Did you (or can you) look into the tank now and see if that is the obvious source of the rust? If it was regularly used (and ~3500 miles per year is pretty regular use) one would not expect the fuel tank to go that bad so quickly. E10 in Connecticut?

[Odoyle]

Having just discovered that my hard fuel lines on my 79 have rusted from the inside out, clogging the line and allowing air to pass through the line but no fuel, this very well could be the issue, the inside of my tank didn't look particularity bad, but after I pulled the carpet inside the car and inspect the lines, I was sure this was the issue, have since ordered new 5/16 and 1/4 steel line from NAPA and will bend them to the previous shape.

[spider2081]

Did you (or can you) look into the tank now and see if that is the obvious source of the rust?

We looked into the tank 5 years ago and didn't think it look too bad. Drained all the fuel and installed new hoses and filters. The Tank has baffles so the rust could have been on the other side of the baffles. We will change the filters again next year and see how they look. They will only have a few thousand more miles on them then. I can't imagine too much more rust being in the tank