I put my truck in park today after driving through town and the rpm's dipped real low and then jumped back up. I didn't catch the number as it was too fast but my truck basically about stalled. I have all the same symptoms of a bad tps and iac (stumbling in the mornings, rough idle, bogging down etc.) but both have been replaced. This is the first time it's actually almost stalled on me. My new plenum (had motor rebuilt and the mechanic did not use the hughes plate, he used a stock one) has only 30k on it so I can't see that as being the problem...yet. Also this morning when I started her up I got a loud air sucking noise, like when you don't put the airbox on right even though it was on tight. I got to work and left it alone and it didn't make the noise on the way back. Any ideas?

 

I've noticed the same issue now that the warmer weather has hit. I go to start the truck, and it doesn't do its normal rev up on startup... kinda stumbles for 5 or so seconds, then gradually works its way up, and makes that really loud sucking noise that disappears after a bit.