What would cause a fuel injected motor to kick back while cranking it? I have a 1999 chevy suburban 4wd 5.7 ltr. I know it needs an intake manifold gasket, but would that cause it to kick back and ruin my starters?
If your truck needs an intake manifold gasket (actually you'll change both sides if you do), get this done and see if it solves your problems. Fix the things which you know need fixed. This may or may not solve your backfire issue, but at least you can go from there.
Timing is the most conventional thought here, though. I believe the 99 still had the GENI SBC which utilized the HEI distributor (2000 is the first year for the LM7, right?). Double check to ensure your spark plug wires are in the proper order (especially if you just did a tune-up). Also, as long as the distributor wasn't removed, the normal position of the HEI should be 90deg (perpendicular) to the longitudinal axis of the engine (axis is front to back, cap of distributor should be left to right), with the wire harness coming off of the driver's side of the cap.