i have a 1988 for f150 and it has great power up until 40 mph. after that it sharply goes down and i speed up slowly. this is a problem especially when i am towing or hauling anything and trying to get up to highway speeds. what can i do to change this. it is a 5.0 V8 with a 5 speed manual tranny
Could be a restricted/plugged fuel filter.
I would say some restriction in fuel flow either filter, injectors, or fuel pump.
I agree on the fuel flow issue. The reason I stated fuel filter is because it's the cheapest to replace, and part of regular maintenance. A good place to start from.
And I agree, start with the least expensive repair first.
Make sure the EGR is operational and not half on the toilet seat!
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