Hard Starting S 10 when warm

My 2000 Chevorlet S 10 2.2L with 106,000 miles start hard only when the engine has been up to normal operating temperature turned off and allowed to cool to approximatly 150 degrease (about 30 to 40 minutes). Other than this condition it runs great. The fuel system has new pump, presure regulator and filter. The system also holds it,s fuel presure long after the engine has been shut off. The ignition has new plugs and wires. IAC has been cleaned and temperature sensor has been replaced. No service engine light.

Any advice Appreciated,

Dave

Reply to
Hartv427
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Have you checked for good spark when this happens?

Bob

Reply to
Bob Urz

From the slight description, you'd not be wasting time to watch the fuel pressure (rig a cheap pressure gauge if needs be) as it sits and cools. Its pressure specs below. It's quite likely it holds pressure, yet not ENOUGH pressure, and could easily show that symptom. Pressure will probably drop below normal operating range as it sits; watch how long it takes to pump back up to normal when you just turn switch to ON--should be almost instantaneous. (Not carved in marble, but I personally like to see the pressure hold to approx. 70% of normal for 60 seconds after turning it off at the end of "your test drive".) BTW: that engine should have fuel pressure of 41-47 psi when running. The temp. sensor which you mentioned had been replaced should be 0.2-0.9 volts, idling and warmed up to operating temp. Luck! s

Reply to
sdlomi2

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