cbiii
Well-Known Member
99 EB 5.4 180k that has always had a miss and poor gas mileage. I swapped plugs initially and after seeing 11.8 mpg i decided to do COPs. After that it ran a bit better initially(~13.4mpg) and then dropped back to 11.8 and eventually developed a sputter. I swapped fuel filter last night and took it out for appx 25 miles. It ran great (minus a slight hesitation which I assume is my trans) and was seeing ~14.6-15mpg. I parked it overnight and went to leave today and I had terrible hesitation, no accceleration and im seeing ~10.7mpg. When i floor it, it just stumbles and never really picks up. No CEL lights or anything after i replaced plugs (~3 months ago)
I rebuilt the vacuum setup coming off of the passenger valve cover with new rubber bits also.
Apparently this is a normal issue for these but ive not seen any solutions.
*also* will not stay idling when started when it has sat and is cold out unless i used heet. (havent checked it with the new filter though)
Granted these numbers are all from the overhead, but it still shows somethings definately wrong.
After new coils,plugs and fuel filter I dont know where to go besides cats/o2s/leaking injector(s)
suggestions?
I rebuilt the vacuum setup coming off of the passenger valve cover with new rubber bits also.
Apparently this is a normal issue for these but ive not seen any solutions.
*also* will not stay idling when started when it has sat and is cold out unless i used heet. (havent checked it with the new filter though)
Granted these numbers are all from the overhead, but it still shows somethings definately wrong.
After new coils,plugs and fuel filter I dont know where to go besides cats/o2s/leaking injector(s)
suggestions?
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