tlcook1

I've got a 2004 Silverado 2500 HD and my Check Engine Light is on and indicated I have an issue with my knock sensors. Does anyone have any experiene replacing these? I saw on Ebay you can buy a knock sensor for about $35 and there is 2 of them in a vehicle. I'm a pretty green mechanic, but I can find my way around if its not too complex of a job. Any good instructions or advice on how to go about changing these? Or should I just have it professionally done?

country_09

it's not as hard as you may think...just under the intake manifold and when you replace em make sure you put some silicone around them so water doesn't get in there

all it is is takin the intake manifold off with all the wires and what not

BabiedSilverado

I'm wondering how you made out replacing those knock sensors. Was it as easy as it sounded? I've an 01 Silverado that has the knock sensor code but I was told by another mechanic that the knock sensor code is usually thrown because of another underlying problem. Did replacing yours remedy the problem for you or did you discover something else is wrong?

country_09

just replace the sensors...if that's the only code poppin up then that's generally gonna be the problem...they get rusted from water gettin in on the backside of the engine especially when you wash under the hood of your truck

tlcook1

I'll let you know tomorrow as I am just now getting around to replacing them. However, I've also been told that if it's the only code popping up than it's your best bet to just replace the sensors. People will tell you there are underlying issue's to it, but I've had two good friends that are mechanics tell me to replace the sensors and they're betting I'll be in the clear.

BabiedSilverado

Thanks for your input~ I've been putting this repair off for some time now due to the varied and contradictory info I've been getting from the shops around my area. My son, who is studying auto-tech at UTI outside of Philly, told me the same things as you have about the sensors getting corroded from water pooling. But, the "local mechanics" are trying to set me up for some extensive and expensive "diagnostics" before they'll touch my Baby. Now I have better info, thanks to you Awaiting your updates! Thanks, Country_09 and tlcook1~

country_09

by just replacin the sensors y'all will both be fine...it took me and my brother 3 1/2 hours to do it with a break in there. we work on our trucks quite often though and have got pretty acquainted with it so it may take longer

shops will always say it's more than you think cause they want the money that goes with the labor they'd have to put into it, you're better off just doin it yourself. it's not hard i promise

tlcook1

I started to make the repair and just ran into a little trouble. Had the intake manifold and everything tore down in about 15 minutes. Replaced the front sensor with no problem. Went to replace the back sensor and it was so corroded the thing wouldn't turn. It looked as if someone had already done this once before and torqued it on way too tight. Hoping to find a way to get the bolt out of there that wouldn't turn this evening.

country_09

make sure you rtv or silicone around them so water doesn't get back in there