2000 sierra 5.3 in a 1962 c10 problems
Truck starts and runs excellent when cold. As soon as it warms up (closed loop) it begins to stumble on accel. I have 60 PSI fuel pressure, fuel system is new walbro and filter, all new lines and tank was spotless.
I have no codes present. I recently changed the left O2 sensor, (DTC code) the spark plugs and the MAP because I thought that was the issue...
Had the VATS removed and the rear o2 sensors...
Any help appreciated. Thanks.
Are you by chance dealing with a fuel quantity problem? Like the size of line in the stock tank is too small?
Most people check the fuel pressure at idle and call it good, but it is very possible to have 60psi at idle, but if the line size is too small, it will not maintain that pressure when engine demand(increased consumption) increases.
And, as mentioned, watching the fuel trim numbers on your scanner should provide valuable information.
if external on a seat tank you are forcing the pump to suck fuel instead of pushing it which has its own set of problems as a wlabro wont suck some 23" of head from the bottom of your seat tank very well if at all, properly
what do you have for a tank vent - is it working properly
where are your fuel filters located? are they clean/new
how did you run the return line and what size?
Last edited by Seeker1056; Mar 23, 2016 at 08:48 PM.
if external on a seat tank you are forcing the pump to suck fuel instead of pushing it which has its own set of problems as a wlabro wont suck some 23" of head from the bottom of your seat tank very well if at all, properly
what do you have for a tank vent - is it working properly
where are your fuel filters located? are they clean/new
how did you run the return line and what size?
there is room to make it an intank install for the pump as the sender/pickup flange hole is lots large ( we are buildign a 61 so I know this for a fact)
you didnt mention what size return line or how you have it installed
I believe 58 psi is needed at all times as the minimum for proper running
you are starving for fuel - see pump location issues
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there is room to make it an intank install for the pump as the sender/pickup flange hole is lots large ( we are buildign a 61 so I know this for a fact)
you didnt mention what size return line or how you have it installed
I believe 58 psi is needed at all times as the minimum for proper running
you are starving for fuel - see pump location issues







