Im riding a 96 ram 1500 Laramie slt 4x4, haven't had her long, just got it from my uncle about a month ago for 300$ currently sitting on 180,000 miles. My uncle was unaware that the motor was replaced at 116,000 (would like to know how to check if it has been replaced) by previous owner. Transmission rebuilt at 174,000 by my uncle but gears seem to be grinding (get into that in another thread). Haven't really had problems with her the couple times I've had her running until I've actually put her to use at my job about a week ago. Lasted me 4 consecutive days before she gave up on me . To get into more detail and the jist of what had happened, after I was done filling her up w/ 87, I got her started and heard a weird vacuum like sound coming from below the air filter it sounded like there wasn't any air flow, it wasnt till i got to the streets i knew for sure something wasnt right, wouldn't excceed past 1000 rpms even at full throttle. A couple guesses were to clean the throttle body, check for clogged cat, and/or iac (Haven't checked these parts yet due to wanting to receive more feedback on the issue) any help would be greatly appreciated thank you!!

 

Plenum checked?

 

Checked it and it looks vacuumed in alot a bit also checked the iac and the end is covered with build up.