What this time? 97 Silverado 5.7 auto won't start.

[97silvershortbed]

I have a 1997 Silverado 5.7 auto 2wd with 170,000 miles on motor

I had this truck for about 2 years and only thing that when wrong was a camshaft sensor was replaced last year.

I was told that fuel pump was replaced at one point also.

While driving last week the truck felt like it misfired a couple times.
Truck sat all night , It was hard to start yesterday,but it start, ran kind of ruff for a while.

The truck sat for the night, went to start the truck, and it would not fire up.
I checked for spark and it looked good to me.

Also tryed sprayed starting fluid and that didn't help.

I checked the psi on the fuel rail and was 60 psi when I turned the key on.
When fuel pump stoped it was 52-53 psi ,then slowly droped to around 40 ish.

In past threads I see alot of you talk about fuel pump problems, coolant sensor,crankshaft
and camshaft sensor, map sensor, coil ,control mods.

So where do I go from here?

[jdmccright]

I'd check the electrical side, namely the coil, cap, and rotor to fix the no-start problem. Check the resistances and look for cracks or carbon tracks that indicate grounding of the terminals.

Aftermarket non-OEM fuel pumps have been known to be of poorer quality than OEM. Once the fuel pump stops running prior to startup, the pressure should hold steady or very near that for a minute or so. If not, then the one-way valve on the return side of the pump is faulty. If the previous owner kept the receipt for you, you'd be golden...buy the OEM pump and give back the crap one for a refund.

[97silvershortbed]

Originally Posted by jdmccright

I'd check the electrical side, namely the coil, cap, and rotor to fix the no-start problem. Check the resistances and look for cracks or carbon tracks that indicate grounding of the terminals.

Aftermarket non-OEM fuel pumps have been known to be of poorer quality than OEM. Once the fuel pump stops running prior to startup, the pressure should hold steady or very near that for a minute or so. If not, then the one-way valve on the return side of the pump is faulty. If the previous owner kept the receipt for you, you'd be golden...buy the OEM pump and give back the crap one for a refund.

Do you think

[97silvershortbed]

Originally Posted by jdmccright

I'd check the electrical side, namely the coil, cap, and rotor to fix the no-start problem. Check the resistances and look for cracks or carbon tracks that indicate grounding of the terminals.

Aftermarket non-OEM fuel pumps have been known to be of poorer quality than OEM. Once the fuel pump stops running prior to startup, the pressure should hold steady or very near that for a minute or so. If not, then the one-way valve on the return side of the pump is faulty. If the previous owner kept the receipt for you, you'd be golden...buy the OEM pump and give back the crap one for a refund.

Do you think the timing chain might be bad?

[jdmccright]

Timing chain is way down the list of possibilities. Quick check is to remove the distributor cap and rotate the engine using a breaker bar on the crankshaft pulley bolt. If the distributor rotates, then the chain is intact. Then use a breaker bar to rotate the crankshaft to TDC. The distributor should be pointing at or near the #1 cylinder wire terminal. If it is pointing at #6, then rotate the crank one more revolution to get it pointing at #1. If it is pointing at any others, then there is a mismatch between the cam and crankshaft and you've got more problems than just the timing chain then. Again, this is quite unlikely.

For it to die so quickly would indicate an electrical issue...to repeat: coil, cap/rotor, plugs and plug wires in that order. Check online repair manuals (Autozone) for procedures on how to test these parts...all you need is a multimeter. Good luck!