Dave26 0 Posted July 16, 2013 What do you guys think would be causing a chuffing sound to be coming from my 300, while under load? It sounds like an exhaust manifold gasket has let go but no black marks show, nor do I feel anything blowing out there. She's a '96 with 640,000 miles and has never been apart. Is a compression test and maybe a valve job in my immediate future? Quote Share this post Link to post Share on other sites
JerryB 10 Posted July 16, 2013 If there's no exhaust manifold leak it sounds more like a head gasket to me. Does it make a chirping noise when you take off from dead stopped?? Quote Share this post Link to post Share on other sites
Dave26 0 Posted July 16, 2013 Nope, no chirping sound. Quote Share this post Link to post Share on other sites
Superdog 5,895 Posted July 16, 2013 broken clamp on a ATAAC hose? Quote Share this post Link to post Share on other sites
Dave26 0 Posted July 17, 2013 Broken clamp... I'll check that in the am. The sound is like a single cylinder blowing it's compression out somewhere and it sounds perfectly normal when you just rev it up when stopped. Under load she sounds like crap. Quote Share this post Link to post Share on other sites
fifth wheel 558 Posted July 17, 2013 Restriction in the air cleaner element.FW Quote Share this post Link to post Share on other sites
Dave26 0 Posted July 17, 2013 The air filter was changed maybe 6 months ago and only has maybe 10,000 miles on it. But, I'll take a look. Quote Share this post Link to post Share on other sites
Dave26 0 Posted July 17, 2013 Problem solved. I had a buddy do a cold start while I stood at the engine. She puffed smoke out of the rear of the exhaust manifold for a few seconds and I could feel the hot exhaust with my hand. Now the fun begins! Quote Share this post Link to post Share on other sites