i bought a 2.8 out a 93 s10 and the hole on the passenger side cylinder head was plugged with what looks like a 3/8 plug but a 3/8 anything wont fit and i need to get this sensor in so i can drop my engine in, well my question is this, the 93s fan sensor was on the center of the plug, on the passenger side near the back of the engine. could i put my old sensor here and just plug it in and get the same results as it being in the head? do you guys have any suggestions on getting the plug out of the head so i dont have to do this? please guys i need help, this is the only thing keeping me from dropping my engine in....please help

 

The 2.8 fan was ECM controlled and the fan switch was merely redundant (failsafe), much like the oil pressure switch for the fuel pump. The later years (F-body) with the 3.1 eliminated the redundant fan switch.

 

Let me see if I understand this...

You said the hole in the cylinder head was plugged, but 3/8" anything won't fit in that hole. So you've taken out the plug, and there's a hole bigger than 3/8"?

If so, then it's probably a 1/2" hole(which many aftermarket cylinder heads have); stock is usually 3/8". If that's the case, then there's a brass bushing(sort of like a plug) you can get that will fit the 1/2" hole, and that bushing has a threaded 3/8" hole through it, and you can thread a 3/8" fan switch or sensor into it.

Regarding the location of the other hole you're talking about, I'd guess that's for the knock sensor. A knock sensor has the same kind of nipple on it as a fan switch, and it uses the same kind of pigtail connector as a fan switch, so installed, it looks like a fan switch, but with a very fat base. And its hole is in the block, below the fan switch.

So the previous owner plugged the hole in the head, and he relocated the fan switch to the location of the knock sensor? Or because the knock sensor looks like a fan switch, are you just thinking that's what he did?

But if your car has/needs a knock sensor, then I'd recommend using each hole the way it's supposed to be used, which means making the hole in the cylinder head useful for the fan switch and putting a knock sensor in its proper location. Otherwise, if you don't need a knock sensor, then I suppose a fan switch will work in the knock sensor's location.

 

Okay let me clean it up, the hole in the 93s s10 engine was plugged from the factor since I guess they didn't use the fan sensor anymore, the sensor on the Side of the block that I was wanting to use is the knock sensor since it sounds like what you described it as, now my problem is I can't get the plug out of the head to install the fan sensor, the plug looks as if it's 3/8 but it's too Small for a 3/8 rachet, the plug is also to big for a 1/4 rachet. I need to pull the plug out so I can instal the fan sensor but can get the plug out as I can't find anything to fit the plug

 

Knock sensor for the f-body was generally in the block, not the head.

 

So you're talking about the size of the square recess in the plug that you fit the tool into to install/remove the plug? If that's what you mean, then there is something that fits onto a rachet, and it's available in different sizes. It's like a stud mounted in a socket... great description lol. It's probably called a "bit," as that's what the sockets for brake caliper bolts are called. Brake caliper bits have a hex stud, but you'd want a bit with an appropriately-sized square stud.

 

Oops, I forgot to post a pic for an example. This is a pic of a hex stud bit set. So you'd want something similar, but with a square stud. They're easy to find at hardware stores or auto parts stores, and you can usually buy them individually, not a whole set.

 

The plug uses a 5/16 bit or whatever. Trust me its gonna strip if you try to get it out. You can try to heat it with a torch and get it out but honestly not worth the trouble. As mentioned above the sensor is more or less redundant and not needed. I did a 3.4 swap in mines and the fan turns on fine without the sensor. Just drop it in and leave it unplugged.

 

yeah thats correct, so i can go to autozone and get the tool to remove it? awesome, thank you!!