Shortly after I bought this Blazer it started making a knocking or ticking sound. It is slow and barely detectable at start up but gets louder and faster when you accelerate. Does not seem to effect performance.


A buddy looked at it and discovered that the guy had rigged a L-shaped heater hose from an exhaust just under the where the air filter is down to under the engine fan. The heat had blown through the hose so I have just been driving it and putting another heater hose on until the heat goes through it and the noise turns.


I am getting ready to sell her and don't want to pass this along to the next buyer so looking to figure our what the correct part is and where I can get it as the local parts stores all said it was a dealer part. Any ideas?

 

The ticking sound is an exhaust leak. The hose comes from the secondary air injection pump located behind the bumper on the passenger side. At the L point where you are having it melt through the hose connects to a checkvalve that has likely failed and is blowing hot exaust back into the hose. Continued driving with an exhaust leak in this area will damage wire looms and vacuum lines. Try rock auto, Part #355050 for Dorman $12.03 AC Delco #12558992 $31.79 but even at a dealer it should be reasonable.

 

Do I need the Air Check Pipe as well. Its about $90 so if can get away without it that would be preferable.

 

Getting the check valve off the pipe is the hard part. You may have to remove the pipe from the manifold to get a couple wrenches on it. Soak it with some penetrating fluid, and it should come loose without damage.

 

Ordered a check valve and finally got around to putting it on. My buddy was determined to get it off with it attached so shower him your reply and we took it off the manifold. Purrs like a kitten again.

 

Glad to hear you got it fixed