hi i just bought a 2001 dodge ram1500 quad cab 4x4 i paid 5400 with 140,000 miles the truck had quite a few problems fixed most of them now my main problem is the truck idle the idle changes from real quite to real loud also theres a real loud hissing noise and when i attept to drive it goin down the road it bogs real bad, ive talked to many mechanics and there all clueless, i put new plugs,belt,air filter,o2 sensor,main computer, fixed booster cable leak,and couple other cracked tubes,also fixed evap system large leak,now my check engine light is back on saying a different o2 sensor is bad havent fixed yet, this truck has been basicly sitting since i bought it 5400 wasted. CAN ANYONE HELP ME WITH THIS

 

Have a read of the Plenum thread stickied at the top of this forum.

Possibly a clogged cat...... do you have federal, or california emissions?

 

just cut my exaust off and still doing the same thing.....ive checked everything

 

Sounds to me like you have a large vacuum leak. what engine do you have?

 

Check fuel pressure, and if that is ok, do a compression test. Investigate the plenum as well.....

 

does sound like a typical plenum problem...

 

The engine is a 5.2. I checked every hose and replaced every one that was bad and still the problem persists, it also it isn't a constant bogging which makes me believe it's not a vaccum leak anymore.

 

Should still check the plenum......