Hello, I'm new here and pretty new to working on engines. I have always done the simple things on my vehicles, but not much more than routine PM.

I need to replace the knock sensors but don't know what gaskets to get since the intake manifold will be off already. Do I need to replace the lifter valley gasket as well?

Also, what kind of gaskets would you recommend? (i.e. material type, brand)

 

Welcome to the forum.

Fel-Pro is a good brand for gaskets. The knock sensors may come with new gaskets. If not then your parts store can probably supply them.

 

Unless you are doing other work that requires the removal of the intake, some have done the knock sensors without removing it... small hands and a lot of patients and it can be done.... search the forum for knock sensor and there is some good info and tools used..

 

Ok, another question about this job. For those who have done it, would you go with AC/Delco or another brand? I have read that other brands may give you the same code / problem.

 

I would suggest the OEM or ACDelco part, they should last as long as the originals, there are several threads in the forum discussing the knock sensors and their susceptibility to moisture...
Use the forum search button at the top of the page and knock sensor, you can also do an advance search and narrow it down to the vehicle model... truck SUV...

 

It always pays off to use the OEM parts in a project like this that involves a lot of sweat and labor.

 

how can one replace the knock sensors without removing the intake? little hands or not man I would love to see that video... especially the rear sensor. I have that job to do coming up on my 02 suburban after just washing the vehicle, but then again, the previous owner probably washed the motor cause it sure is clean under the hood .

 

Knock sensors are sensitive to moisture? How so? 1992 boat has one on the passenger side (of a boat, driver side car) head for a 351W, still works fine...

 

from what I have been reading up on, the oem seal ( rubber plug on top of sensor)leaks water thus ruining the sensor, according to the TSB after replacing new sensors you put a bead of RTV around the new rubber plug but not all the way around it leave an opening at the rear of each plug, and to remove and leave out the foam in the rear of the intake manifold. I guess corrosion, , they are very moisture sensitive from what others say also. I can attest to that cause it ran great no codes until it was washed.

 

i just did this job yesterday. i used the felpro kit, nice metal gaskets with rubber inserts. replaced both sensors as well as the connecting plug that connects the sensors. i cleaned up the manifold and the channel as well with some degreaser. also put the bead of of rtv around the sensors to hopefully keep the moisture out. i didn't leave an opening at the rear of each plug though or did i take out the foam. not sure why to do this but i wish i wouldve seen this yesterday