Help! Removing Knock Sensors?? UGH!!

[Donne Trav]

This is not as easy as I was led to believe. The space is too small for
using vise grips or channel locks. I got a monkey wrench to get a pretty
tight hold but no room to get leverage to turn the wrench. Went to parts
store to get a deep socket. My 3/4" and 13/16" were too small.I returned
from the parts place with a 7/8" deep socket only to find out it was too
large!! DON'T TELL ME ITS F-----G METRIC. What is an American made
vehicle during using anything metric?? I've found that the C-4 uses both
standard sizes and the metric! Again, I'm too old for all this sh--! Next
time I'll just let the man do it! Anyone no what size socket will fit the
freeking knock sensor. Also, do I have to open both sensors so as not to drench the Opti when I crack open the water pump? I'm a little tired and frustrated right now — forgive me. THANKS ALL

 

[jrzvette]

Not sure what size the knock sensors are but I will tell you no matter how well you think you've drained the coolant, cover the opti with shop rags or plastic bags before craking the water pump free. Also, if you have access to a compressor, blow out the cooling system once the sensors are removed. And check the opti carefully. If it looks like it needs to be replaced now is the time to do it. One more thing. Befor you replace the WP attach a drip tube to the weep hole. Make sure it's long enough so that you can let it hang down below the opti. This way if the WP springs a leak it won't dump coolant on the opti.

 

[vetteoz]

DON'T TELL ME ITS F-----G METRIC. What is an American made
vehicle during using anything metric?? I've found that the C-4 uses both standard sizes and the metric!

Knock sensor is 22mm
The C4 was all metric except for any existing GM parts used ( engine mainly ) Anything that had to be made especially for the engine was done in metric.
Which is why your Alternator has metric bolts holding it to a imperial engine

 

[93Rubie]

Most modern cars post 1990 including American makes are mostly metric, I can't remember when I used a SAE sized anything on a car recently. I will give you a bit of advice, RELAX. I work on this stuff for a living, getting worked up about it makes it worse. Walk away for a while if you have too. I have learned this the hard way. Patience is key, easier said than done I know, but it is the truth. Get into a tight spot, think about the problem and ask others, way better than flipping out. Believe me, I flip out enough as it is.

 

[kenmack]

Tricky part

Draining it is no problem.
When you refill and have to use the bleeder screws above the opti on the intake it gets tricky.
I put a big hunk of plastic down by the opti and then stuffed all the shop rags I could on top.
Then I put another piece of plastic over top.
NO PROBLEMS
p.s. THE ENTIRE PLANET USES METRIC !!!!!!
I'm old school too but it's goin that way like it or not.:eyerole

 

[boomdriver]

yes, 99% of the c-4 is metric and many of the imperial engine parts are re-tapped for metric thread.
Metric is so much easier to use when doing the math, for those that have to think about whats the next size up from 7/16"?
I'll get over metric. I'm used to that from the bike building days in the 70's.

It's torx that gets me a little twisted up...

 

[WhalePirot]

It's torx that gets me a little twisted up...

Ha Ha.. Torx... twisted.. I get it!

 

[boomdriver]

glad today is better !

 

[So Bay Vetter]

I didn't remove my knock sensors but then, I was already replacing the opti. Bag the opti, use plenty of towels (old bath towels are bigger and more absorbent than shop towels) and forget messin' with the knock sensors . . . just my 2 sense.

 

[vertrx7]

That's actually good advice on maybe not doing the knock sensors. I've read some guys suck the water out with a wet/dry vacuum cleaner.

I got one of the sensors off no problem. The other one broke off and the stub of the bolt remained in the block. Try that for frustrating. Many methods suggested but none worked. I took the car to the local garage that I trust...on the car trailer...no WP attached, no water in the block, etc.

Though I tried everything to get the stub out, he did it with one of those sockets that go around the stub and bite into it. I tried that with no success laying on my back. He did it under the car on the lift...$80 later for 10 minutes work.

I'm now wary about those knock sensors!!

I'm in VA, so if you need some help with something, give a shout out. I think I hold the record for working on my WP...going on two years now. Always something else to fix!