So I have neglected this issue on my sons blazer but I’m coming back to it.

It is a 2000 2 door 4x4. The issue is that there is a thumping type noise coming from what sounds like the fuel tank area. My guess is vapor canister solenoid but I can’t seem to find that as a symptom.

It runs fine but will occasionally throw a CEL.

Has anyone heard this before? Am I on the right path?

 

What are the codes?

George

 

P0174 typically.

 

P0174 means that the fuel delivery system is compensating for a lean condition so there is unaccounted for non-metered air in the system such as a vacuum leak. A faulty evap system can do the same thing for the same reason. What are your fuel trims, each bank separate, short term and long term trims, with +/- sign, at idle and 2500 rpm.

George

 

You need to let him out! (Sorry I couldn't resist)

 

I wanted to resurrect this thread because my 2000 Jimmy has the same symptoms. After driving 3 or 4 miles I might hear a thump. A few miles later I might hear it again. It seems to be coming from the gas tank area. I have no codes - just this noise. It kind of sounds like when a 55 gallon metal drum when it expands/contracts. Anyone have any thoughts?

 

Glad I’m not alone on this.

Unfortunately I have not had time to address my sons Blazer. Doesn’t seem to be causing any issues, just annoying.

 

Check the rear spring shackles for rust through! Caused some strange rear noises in mine.