1999 Chevrolet Silverado Is Hard To Start

Problem with my 1999 Chevy Silverado 1500. Engine size = 5.3 L. Question;
I have a 1999 Chevy Silverado that i bought about 2 months ago. Ever since i bought it has had a hard time starting except for first thing in the morning. I had the fuel pump replaced and have been using Lucas Injector Cleaner with every tank of gas. The problem never seemed to get better so i started to read online and i came across over 5 different cases where guys had the same exact problem and they replaced the fuel pressure regulator and the truck has fired great ever since.

I went out and bout a fuel regulator and put it on and now the truck starts great every time, but now the fuel pump is humming like it is running constantly while the truck is idling. It sounds like the pump is running way to hard and it is vibrating in the gas tank and I'm not sure why this is happening. There seems to be more a than usual amount of white smoke coming out of the exhaust which tells me that it is burning to much fuel. I hope this is enough information for you its kinda a hard problem to describe. Thank you.

The pump running all the time is normal. Electric pumps run constantly. Changing the regulator should have nothing to do with changing the sound of the pump, unless it is not a factory regulator and possibly rated at a different pressure than the original.

That may also explain the smoke that makes you think is it running too rich. If the pump is extremely noise, then it may be starting to go bad. White smoke can also be that it is burning a little coolant.

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1997 Chevy pickup 4.3 v6. Question:
I have a 1997 Chevy pickup 1/2 ton 2 wheel drive with a 4.3 v6 engine, extended cab 1500. Wanted to know can I change the motor to a 350 v8 carburetor or fuel injector motor without using a computer brain & if it can be done. Whats the best one to use the carburetor or fuel injector. My truck has 359.293 miles on it. I want a bigger motor. What do you recommend. Thank you Robert.

As far as swapping engines to a V8, the actual fitting part is quite easy as the V6 uses the same motor mounts as an 8 cylinder, so it would just drop right in. If you chose to go carburated, you would have to switch transmissions to a unit that is not electronically controlled. It would be less expensive to put in a fuel injected 5.7 out of the same year truck. You could keep your current transmission, and you would just need the engine harness and computer from the V8. Also you would have to switch fuel pumps and the fuel lines would have to be changed to the correct ones for that engine. If you could find a donor truck that you could take everything off of, that's always the easiest way to do swaps.

Chevy Silverado. 5.3L Vortec.
Work done to repair = changed spark plugs / wires and distributer cap and rotor. Question: Seems like a misfire when cold but ok when warm. Changed plugs seemed to cure for a couple of trips then started again. Change wires and distributer/cap seemed to be cured then started again. Checked for trouble codes and there is none. Runs fine when warmed to operating temp. Stumped? If there is a misfire should get a code or pretty much any other problem but none show up.

Answer: This sounds like you may have a leaking intake manifold gaskets. These are know for leaking. They have been re-designed by GM to correct the problem of they shrink over time, do not seal when cold, then seal when warmed up.

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