Recently my '79 FJ40 started leaking fuel from the fuel pump so I got a new pump and spacer and replaced it myself. I drove it around town for a few days without problem then had a reliable mechanic just do some brake work and general maintenance for me. When I got it back from the mechanic and was on the interstate going about 60mph it started jerking and felt like it was gasping for fuel. I was losing power and rpms and I downshifted when I could because I was afraid of it dying on the highway. I limped home at about 35mph (with normal rpms) and really didn't have any issues in 3rd gear but trying to accelerate or go up a hill caused the same issues. The week before my fuel pump went out I had a weekend trip on the interstate doing 70-75mph the whole time without any issues and I've never had this happen in the few years I've had my FJ.
Any help on why it might be acting up when I am giving it throttle? There are two lines coming from the gas tank to the pump and the pump has an arm labeled "in" so I have the line with the fuel filter going to that and the other line to the remaining arm. There aren't any leaks from the spacer or the pump and driving it today it was fine about 90% of the day but I had one spell of the same jerking or lugging as I was accelerating. Any help is appreciated, thanks.
Any help on why it might be acting up when I am giving it throttle? There are two lines coming from the gas tank to the pump and the pump has an arm labeled "in" so I have the line with the fuel filter going to that and the other line to the remaining arm. There aren't any leaks from the spacer or the pump and driving it today it was fine about 90% of the day but I had one spell of the same jerking or lugging as I was accelerating. Any help is appreciated, thanks.