As the title says, my 99 Silverado 1500, that has 188700 miles, is giving me some issues. Have to crank it at least two times to get it to turn over, if you do not let it run for a few minutes it will not surpass 5 mph but runs at high RPMs until it jumps then is better. If you push down on the gas peddle to quick, it will bog down. Have a couple of check engine lights on. Both banks, bank 1 and bank 2, run lean. Fuel pressure sensor is sending a code also. But I believe that is unrelated. It is also back firing quite a bit. I have cleaned the MAF sensor, throttle body and replaced the fuel filter. Could probably use a tune up. Oil has been changed every 2500-3000 miles. I'm thinking it could be throttle position sensor or fuel pressure regulator? Any advice or opinions would help. Anyone else have this problem? Thank you.

 

If it feels sluggish when you step on gas I'd be interested in checking fuel pressure and exhaust back pressure. But, you say both banks are lean so I'm wondering if you have an intake leak at the intake manifold gaskets. It's drawing in to much air for the fuel mixture. And that may be relating to back firing because the ECM is going to adjust fuel for lean condition detected by o2 sensors. You may also have a check valve bad in fuel pump causing it to lose pressure over night and that's why it has to crank a few times in order to fire. So many things and so many ideas. Hopefully this gives you a couple more things to look into to help pinpoint. Just don't throw any more parts at it until you have a better idea. No sense in replacing parts that don't need to be.

 

My truck has this same problem (2000 silverado 1500 5.3L). It is really annoying when I start it in the morning and pull out onto the road and then I cant accelerate past 5mph.

I think I have a leak on the exhaust manifold which may be messing with the o2 sensor allowing air to leak in before the exhaust pipes heat up and expand to seal the leak better