40series

how hard is it to place a knock sensor? i need this before i get a tune i heard im looosing about 30 hp's. Im pretty good with tools but its getting cold here in MI-too cold.

01GMC5.3

iTrader: (7)

all you got to do is take your intake off. It ain't to bad. I would say about a 3 hour job it is pretty straight forward

charcold-bowtie

iTrader: (10)

I would replace the sensor harness while there too, as well as make an RTV dam to help keep water off them

budhayes3

iTrader: (19)

+1, there's a TSB in reference to the RTV dam, otherwise water can get down on and into the knock sensors and cause corrosion which can affect the knock sensor signal as well as trip a check engine light and code. The knock sensor sub-harness is prone to corrosion and drying out also, definitely spend the few extra bucks and get that too

03sierraslt

iTrader: (22)

Its not hard, if you know what to do its more like a 30-45min job (thats taking your time too) Once done put some RTV around the rubber seal/grommet to keep water from being able to enter. If water makes it past the rubber seal then it can lay around the knock sensor causing them to go bad and electrical issues.

Mrgoodwrench3

The LS Engines are such a pleasure to work on. GM is light years away from other mfgrs with this motor. The intake is actually a simple job. I have it off in 8 minutes. It's what you do when it is off that is important. Replace both knock sensors and torque new sensors to 15 ft lbs. Be sure to replace the harness too. Do yourself a favor and use AC Delco parts. Not any Autozone, Pepboys parts etc....

budhayes3

iTrader: (19)

Yes, yes, yes, almost forgot...knock sensors can be very touchy, and you don't want an inferior aftermarket one, and you don't want to over-torque one. Making a knock sensor too tight can cause it to get over sensitive and sense a false signal to the PCM which will in turn pull up to 8* of timing.

40series

hey man i been studying how to remove the fuel rail as a assymbly yikes alot of these guys say they can take the manifold off in less than a hour ? wtf im goood with tools Justin with Black Bear told me i need to address that issue - GM techs told me after 50000 miles i needed one but not untill i got seriuos with my mods have i relized that im loosing mybe 30 hp [says justin ] anyway i gather alot of marking what came from where and alll when removing the fuel rail -

40series

is that the enire intake man. removel or just ......?