Hesitates to start

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_STUCKY
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Hesitates to start

Post by _STUCKY »

04 s10. 4.3. 84,000 miles.

When I get in to start the truck, I seem to have to crank and crank on the poor thing before it will start. It doesn't do it all the time, mainly if it has sat for a while, like multiple hours or overnight. If I turn it off and try to restart it, it usually fires right up.

I haven't really had time to research much, let alone have time to work on it. Initially I thought fuel pump, but now I'm thinking it's something else.

Suggestions?
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HenryJ
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Re: Hesitates to start

Post by HenryJ »

Go back to thinking fuel pump, or maybe injectors?
Do the fuel system checks to determine what and where.

I suspect either a bad check valve in the fuel pump, or stuck poppets and a leaking injector. The tests will tell the tale.

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Re: Hesitates to start

Post by ApproachMedium »

Most likely a bad check valve in the fuel pump. We chased everything possible under the hood when mine had this problem because I was stubborn to change the fuel pump. It was the fuel pump lol. Though i did find I had a leaking injector which that didnt hurt to replace at the time.
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HenryJ
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Re: Hesitates to start

Post by HenryJ »

Usually the leaky injector will mean a rich start problem. Check valve in the fuel pump will have the plugs read clean.

"Speed doesn't kill, suddenly becoming stationary does." - Richard Hammond
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Torskdoc
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Re: Hesitates to start

Post by Torskdoc »

My '02 does the same thing almost with every start. I've gotten used to turning the switch on long enough for the pump to switch off(count 1000 and 4), turn off the ign switch, and turn it on to start.

I'm gonna run it until the hiway mileage drops to under 20mpg.

But 1st I have to fix the constant on SES light that won't go out. See my post about Changing Motor Mounts and SES LIGHT ON.

Larry
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1995 GMC Jimmy 4Dr. SLT
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Re: Hesitates to start

Post by JaVeRo »

Mine was a fuel pump also. Check the fuel pressure, turn the key on and let the fuel pump cycle. If it drops back to zero after the fuel pump cycles, then there is your problem. It could be the regulator but most likely the fuel pump.

James
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2002 S10 Crew, 2003 S10 Blazer
2006 K2500 5 speed