Knock Sensor

[Mango]

Hey All
My 1989 Suburban the 1500 4 x 4 just rolled over 200,000 miles as the original knock sensor should I replace it it’s running fine should I leave it alone is it going to be stuck leave it alone I can get an AC Delco one cheaper than the NAPA one that’s weird thanks in advance

 

[Redfish]

I kind of feel like if it ain't broke and it ain't part of regular maintenance...don't mess with it.

I was worried mine was going to be difficult to remove but it was not as bad as I expected. Not a difficult job but you are going to get coolant on yourself when/if you remove it.

 

[Ricko1966]

Hey All
My 1989 Suburban the 1500 4 x 4 just rolled over 200,000 miles as the original knock sensor should I replace it it’s running fine should I leave it alone is it going to be stuck leave it alone I can get an AC Delco one cheaper than the NAPA one that’s weird thanks in advance

Test your old one,don't eff with it if it tests fine. It probably is going to be stuck and a huge PITA! So test it.

 

[Mango]

How to test it

 

[Ricko1966]

How to test it

Do you have a timing light or a multi meter?

 

[Mango]

Yes I have both

 

[Ricko1966]

Put your timing light on it whack the block near the oxygen sensor with an big combination wrench look for the timing to change briefly.

 

[gmbellew]

The ECM self tests it. If it doesn’t see knock counts during the self test, it will throw a code. No reason to mess with it if it isn’t throwing a code.

 

[Mango]

No codes

 

[gmbellew]

No codes

Then I would just leave it be!

 

[Vbb199]

Fwiw I had a knock sensor on my 89 suburban that passed self test but was pulling timing all the time for no reason. Replaced, TQ'd to spec, checked knock response with hammer and Datalogging device to see registered knocks.... it was good.

 

[Vbb199]

Might i add it was OEM with either 2xx,*** or 3xx,*** miles.

Nobody knows the exact mileage of the truck, but based on the fact the brake pedal rubber is missing all together, its gotta be over 300,00 when I did that sensor.

The condition of brake pedal rubber is how you determine the age of the squarebody in question and dont let anyone tell you otherwise.
100k - the rubbers there and design still there.
200k - its got a hole worn in it
300k , its missing

 

[Vbb199]

400?? You've decided its time to replace it hopefully, because you and the truck outlived the P/O

 

[TotalyHucked]

The way I look at TBI trucks, if it's running fine, DON'T TOUCH IT. Sam can attest to that lol. They're finicky and aftermarket parts are super iffy these days, I wouldn't touch it unless you start to have problems/codes