car in question:
1990 civic with b16
walbro 255 intank pump(second aftermarket pump other failed after 3-4 months)
stock fuel system other than that
no codes


ok first my car runs ok when warmed up and a full tank for a few miles, but if i drive it for a while 25+miles or the fuel tank is half empty the car with stutter and bog.

like i posted above i had this problem with the stock pump and the first aftermarket pump i put in it would run good but when it got below half a tank i would full it up and it would take 6 gallons so it's like my tank is spilt in half.

new parts
brand new in box distributor one year ago
new wires 2 months
new plugs two days
new o2 sensor 1 year(this maybe it to)
main relay re soldered 6 months ago looks good still.

my idea's: tell me if any of these would cause this
1:bad fuel pressure regulator it's stock

2:bad wiring shorting out the pump the wiring intank is good. i thought it might be this after the first one died so soon but when i pulled it it was tight.

c3:logged fuel tank

4:would a bad fuel pump relay or bad fuel sending unit(gas gague level in tank)

 

when you installed the fuel pumps did you use the original rubber line connecting the sending unit and the pump? i had a customers car that acted the same way, turned out to be a small leak in that rubber hose. when the tank was full, the line was submerged and couldnt draw in air. as soon as you drove 30 miles or so and used a little fuel, the hole was exposed to the air pocket at the top of the tank. just an idea. g/l

 

make sure the pick up is facing the right way, if its upside down or side ways it will only be submerged to half a tank of fuel. my friend had this problem in his B16 EF sedan....took us about 3 hours to figure out what it was....

 

see if the sock fell off the bottom of the fuel pump pick up tube just did it to mine yesterday in my 95 h22 hatch.

 

Try the above and make sure the fuel pump is installed correctly / low enough

 

check to make sure the fuel rail is not cloged

 

I used to have a similar problem with the b16 in my crx. it was my injectors. They were just old and couldn't take it any more, especially on the highway. I put in some dsm 450's and adjusted the fuel map in my ecu and problem is non existent