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  1. Bell Housing Knocking

    OEM Issues
    Hi all! Lately I've been having a fairly new set of issues. And I am not sure if they're connected but I'm assuming they are. I've recently been hearing a knock that raises in frequency and slightly in volume along with RPM's. Fairly certain I've isolated the noise at the bell housing. I checked...
  2. Knocking noise after purge selinod replaced

    I replaced purge vent selinod after research and having it hooked up (07 chevy trailblazer) and now it starts like it should but there is a knocking noise while running. Is this because the compression changed? I am not very mechanical and before I take it and drop a ton of money for someone to...
  3. Engine knocking fixed with SeaFoam then came back

    I need some help. I thought I fixed the knocking issue but it has come back. I was towing our travel trailer back to the storage unit with the gas light on. Just before I got to the gas station the engine started knocking. I filled up and the knocking continued. I got home and checked all...
  4. bad knock/loss of power

    I have a 03 GMC Envoy with about 110,000 miles on it. I know the fan clutch is bad and its been ticking for a while. The motor just started knocking here lately. It will start up no problem and idle smooth as glass but it will knock and has no power. It almost seem like its holding its self...
  5. Bad engine noise

    OEM Issues
    I recently replaced my engine with a remanufactured I6. Just recently it started making really loud knocking sounds. The loudness and rythm change with RPM's. When driving on the highway, when I accelerate slighty I can barely hear it, but when I let up on the gas it get extremely loud and then...
  6. Knocking sound

    On my 2004 Envoy XL, there is a knocking or tapping sound for 15 to 25 seconds, after starting the engine. It does not happen all the time, but mostly on cold start. This sound is coming from the Passenger side rear of the SUV, behind the 3rd seat and underneath the side window, and behind the...