I replaced the tensioners, top and bottom and chains about 10,000 miles ago. Key word is I, and I'm not a crackerjack mechanic. But on the other hand, it never backfired before...If I have someone else replace the intake manifold (likely), I'll have him take a look at the tensioners...Thank you for the heads up.

 

Have them check the cam timing to make sure it's correct. Backfiring through the inlet manifold is usually caused by lean mixture or incorrect valve timing.