hi all. my fuel level sending unit is on the way out. it will show full way too long, usually until about the tank is half empty. then it slowly get more accurate at about 1/4 to 1/8th of a tank remaining. when I drop the tank to change, I figured change the fuel pump and tank as well along with the filler neck insulator and pipe to trunk floor seal. yes.... and straps. I plan to purchase the all in one hanging unit with fuel pump and strainer. that shows 3/8th inch line but when I was looking at just pumps it gave a choice of 5/16 or 3/8th's. why the difference? was 5/16th's for the 4cyl.? also, does anyone know what the grommet is called for the hole next to the fuel pump opening. the hole the pipe/tube is just pressed in. do it all while it's out. thank you.

 

Sorry I can't help as I don't know for sure, but you could contact the supplier and ask them.

If I had to guess, I'd think you maybe on to something with the 4cyl theory.

 

just did a search for a 89 4cyl and the fuel pump does come up as 5/16. thank you.