When I put my 2002 silverado 1500 4.3l automatic in gear and step on the gas pedal it is very slow to take off. Once up to speed say 45-50 ...

When I put my 2002 silverado 1500 4.3l automatic in gear and step on the gas pedal it is very slow to take off. Once up to speed say 45-50 i have throtle response. it just happens when first starting out. Any ideas? I have changed out the inline fuel filter and the in tank fuel pump has been replaced. All input is appreciated.

Sounds like it's not getting enough fuel or air. Do you have a CAI?

Just what is stock, no aftermarket CAI.

Your timing chain might have something to do with it. Could be stretched out. There are a ton of little sensors you can look up for it and just stat going from there.

Someone might be able to narrow it down with a scanner that will read your fuel spikes while driving. That way you know if you're running lean or not.

Thanks for the input.

I had a 99 Silverado 4.3 and I had this same issue. No power until I was already driving. It never felt as bad because the issue started off slow and got worse. It eventually started to stall. I had to have it smog and didn't pass because it had a mis. My mechanic later discovered the timing chain stretched out and was out of timing. Put in time and truck felt like new again. Just my experience

I seafoamed my engine and my trottle response did increase plus with the age of your truck it would be good to give her a cleaning anyways. I used the method talked about in this thread.

Seafoam smoke show