Five problems related to manifold/header/muffler/tail pipe have been reported for the 2001 Chevrolet Suburban. The most recently reported issues are listed below.
When vehicle is idling while not moving extreme amounts of exhaust fumes are entering the cabin area through the ventilation system. This is due to defective exhaust manifold bolts which are breaking allowing the exhaust manifold to open and allow fumes to enter the engine compartment which results in the exhaust fumes entering the passenger cabin area through the ventilation system. This is a health issue for passengers inside the cabin breathing the toxic exhaust fumes. This should be a safety recall on gm to fix the problem due to poor engineering design and for using poor quality components which fail for no reason. Also this is an extremely dangerous situation for passengers inside the vehicle, which have to breath the dangerous exhaust fumes. Gm should be made to repair all vehicles affected by this problem which were designed and engineered with inferior parts which are causing this dangerous situation for millions of people across this country.
Exhaust and manifold cover bolts are too weak and the heads break off. I had to replace all of them with racing bolts. Much better now.
The bolts that hold the exhaust manifolds down are breaking off at the heads and causing exhaust leaks. Which are in turn causing my catalytic converters fail prematurely. I hope gm fixes this massive problem with there LS v8 engines!.
Noticed no bolt head on drivers side rear exhaust manifold, was not sure if it was supposed to be there. Then found another bolt head in skid guard during oil change, this was from the front bolt of same exhaust manifold! the heads broke off cleanly for no visible reason. Fixed front bolt but rear one reqires exhaust manifold removal at cost of $400. 00. This could be very dangerous if more break!.
The vehicle displayed a loud noise that sounded like a muffler and or vacuum. The vehicle was taken to the dealer in which they had taken diagnostic tests but wasn't sure what the problem was. They then stated that there was a known problem with the intake system in which air would surround the engine. The problem seemed to worsen each time the vehicle was in motion. The right front window was inoperative due to the motor going bad.