Start engine and it runs normal in the beginning, 20minutes into it running normal it starts to run sluggish and rough and then it dies. When it does this I hit the throttle and it does not help and sounds like its starving for fuel. Replaced fuel pump and filter, oil change with filter, air filter, new plugs, changed anti freeze, none of that made a difference. Did same thing. After about an hour tops, it would start back up as nothing was wrong. Then it would do this over and over again. Exhausted of all I could come up to find the cure for this. HELP! Thanks. Dan
Dan, only the fuel pump MIGHT have fixed the problem. Not sure why you thought the rest would help.
A few details about the car would be really helpful but I’ll take a stab at it and say your crankshaft position sensor (CPS) is failing.
Is the check engine light on? If it is, what codes does it show? If there is no CEL nor codes, I’d say it IS the CPS. What engine is in the SUV… a 5.3 liter V8 maybe? The CPS is behind the starter in the rear of the engine block. The sensor is cheap but a little hard to get to.
Next time it won’t start, spray some starter fluid into the intake and crank it. If it runs for a moment and dies, it is a fuel problem. If nothing happens that’s another hint it is the CPS.