S-10 Forum banner

Here we go

502 Views 36 Replies 6 Participants Last post by  Ed Mc
How it went-

Ok so yesterday I drove down to tennessee to meet a guy to buy an 86 S10 Blazer like my other one but this one runs. He drove it all the way from Montgomery Alabama to Nashville WHILE towing a full size pickup truck on a dolly. I bought it for 2150$ with a 3/4 drop kit.

MyQuestions -
Ok now here’s what i’m wondering. The guy says it has a 3.4 out of a camaro. I got some pictures and there’s some stuff I just wonder if could be corrected like the map sensor is just sitting there with open wires and there’s a thing with a bolt plugging it. Is there somewhere that it goes or is it because it was a 2.8 originally and it doesn’t have that stuff anymore. Idk help me out.
Motor vehicle Hood Automotive exterior Automotive tire Gas

Automotive tire Light Motor vehicle Tread Automotive design

Vehicle Light Motor vehicle Automotive tire Car

Automotive fuel system Motor vehicle Automotive tire Automotive design Automotive exterior

Wheel Automotive parking light Tire Car Land vehicle

Car Hood Motor vehicle Vehicle Automotive tire
See less See more
  • Like
Reactions: 1
1 - 20 of 37 Posts
Can't answer your questions but that one is a beauty, nice buy.
There's supposed to be a horseshoe-shaped bracket the air cleaner, right about where that hole is, where the bracket on the MAP sensor would just slide down into, and sit there on the side. Looks like that's all messed-up and they're using a chunk of electrical wire to hold up the sensor. I'd plug that hole.

You could relocate the MAP sensor to the firewall, it's commonly done and would look cleaner. Just make a bracket or heck you could even zip-tie it, and it'd look better than it does now! The MAP is pretty much self-contained and won't be affected by how it's mounted. It just needs the vacuum line and electrical connection and it's good to go.

Take a look at the driver's side of the block. If it's truly a 3.4, it'll have some "X" reinforcement castings on the block, also there will be a big "F" that you can't miss. I'd imagine that stands for "F-Body".

The plugged-off vacuum line could be for the EGR, does it have an EGR valve and if so, is it connected?

If the other end of that plugged-off line goes to the TBI, maybe it's actually the hose that goes to the EGR control solenoid. Does it have one of those? I couldn't make it out in the pics.

Someone here should have a vacuum diagram for a 2.8 TBI, it'll be the same hookup for a 2.8 TBI system bolted onto a 3.4.

BTW if you have small exhaust (1-7/8"), you'll get an amazing increase in power by improving that. Go to 2-1/4" back of the cat, with a turbo muffler.

Another big improvement for the 3.4 swap is to bolt on a TBI meant for a 4.3 90-degree V6. This TBI happens to have 1-11/16" throats, which is the perfect upgrade size for a 2.8. You do have to pull the intake manifold and take it to a machine shop to have the twin TBI intake holes bored out to 1-11/16". If you don't, the larger-diameter throttle blades of the 4.3 TBI will hit the smaller holes. And no sense having a big TBI if it's going thru 2 little "wheezy" holes, eh?

Those 2 mods give an incredible increase in 3.4 performance. I have a '90 Trooper with the Camaro 3.4, and for the longest time I ran the stock exhaust. When I finally did the mod, it was like having a new engine in there. Couldn't believe the power. Already had the big TBI (a Holley Big-Bore, which is NLA). But even with the Holley, it needed a better exhaust and I was very pleased. Still runs great after doing the swap over 21 years ago.

This is a good page to read for performance tips for any Iron-head 60-deg V6, if and when you're ready to do things to it:

Anyway, enjoy your "new" rig, a much lighter S10 should be really fun to drive with a 3.4 in it!


Wood Personal protective equipment Glove Metal Fashion accessory
See less See more
  • Like
Reactions: 1
A lot of good information. Thank you very much. I’m probably not gonna mess with the motor I got an ls ready whenever the little 3.4 gives up on me. Are these egr or anything or what are these doing? the first picture is a thing coming off of a line that goes to the second pictures vacuum ball. and the third picture is something. idk but it was sucking wind.

Automotive tire Motor vehicle Electrical wiring Gas Rim
Automotive tire Water Gas Rim Automotive wheel system

Automotive tire Motor vehicle Wood Tread Automotive wheel system
See less See more
Yeah, that is the line going to the EGR valve, it shows right in your pic. I don't see why they disabled it, the EGR really doesn't affect driveability unless there's something wrong with it. And you're not gonna get any more performance by disabling it. Plus you'll get a Check Engine light.

I'd plug it back in and see if things are working OK, if not up to you whether to fix or leave disabled. At least we know what it goes to!

Looks like you got yourself a nice vacuum leak off the ball, I'm sure those cracked vacuum lines don't do much for smooth idling or whatever.

I'd agree, an LS swap will give you a lot more power than the Little V6 that Could! But it'll still be fun to drive around for a while. Definitely snappier than a 2.8!
You got me! Just a single-wire connection, it would seem. Anything electrical on the truck not working? Gauges, etc? It would do to track down a wiring manual for that. It does look like a factory connector, though.
Ok i plugged that back in and i’ll go test it here in a few to see if anything happens. it does have a service engine soon light on but it runs really good. Just some suspension and steering work and it’ll be more reliable than a new car. The only thing that doesn’t seem to work is the inside lights like dome and under dash. might be a blowed fuse or just bad bulbs idk. I appreciate your help and i will keep you updated on this blazer

Can you look at the first picture of the 3 that i sent of that egr thing because now i’m wondering about it.
Wheel Tire Automotive parking light Car Automotive side marker light
See less See more
  • Like
Reactions: 1
I also have this blazer here it’s an 87 i’ve made a few posts on here about it just think they’re cool little trucks and basic as can be and just going up in price up where I live in Indy.
  • Like
Reactions: 1
I wonder, is that "ball" a vacuum reservoir for the cruise control? At any rate, it looks like you should be able to pull that broken vacuum line off the ball and replace it. Also the other 2 lines at the "tee".

I'd replace 'em back to wherever they go, if it's accessible. Otherwise at least cut back to good line and just use a small coupler to splice in the new stuff. It would definitely be the source of a vacuum leak, though.
Ok so i got those vacuum leaks fixed (the ones i know of) and it runs a little better and the check engine light is off but it still isn’t running perfect. Would any of these plugs that aren’t plugged in be some of the problem pic 1 and 2. and is there a reason they had the exhaust thingy blocked off unlike the other side where they have that flexy pipe on it going to the breather? If those aren’t the problem then I think it might have some more vacuum leaks somewhere under all the mess.

Motor vehicle Automotive tire Rim Gas Auto part

Automotive tire Hood Bumper Automotive exterior Motor vehicle
Automotive fuel system Motor vehicle Automotive wheel system Metal Auto part
See less See more
OK, that 1st picture is the knock sensor. It's no wonder it doesn't run that well, with that disconnected! That's what sends a signal to the ECM and works with Electronic Spark Control to make sure the timing is correct when you're driving it.

I'd definitely recommend reconnecting it!

The other connector looks like it's for the Smog Pump solenoid. It would seem that they deleted the a.i.r. injection pump (aka "Smog Pump") and plugged the pump end of the hose.

It's purely an emissions thing, shouldn't affect the way it drives. I'm not even sure if that being gone and disconnected would pop a Trouble Code.

Here's a good thread on the "proper" way to do a smog pump delete:

See less See more
Why would they have it unplugged? would there be a reason or just idiots?
would there be a reason or just idiots?
Yes! :unsure::sleep:🤪😜🤓🙄😬😵🤡🤡🤡🤡🤡
Ok i’ll go plug it in and see what happens
I believe you'll find it runs a lot better, long as the Electronic Spark Control (ESC) system is operating correctly.
Ok here’s the deal now. the starter is so close to it i can’t plug it in. could i trim down the stud on the starter for that little bit more clearance it needs or is that why it ain’t plugged in?
Well, probably that's why. The starter stud might be the easiest to do, long as the connector will be far enough away from it.

On my 3.4 swap into the Trooper, the starter was on the driver's side and there was no interference with the knock sensor being back there.

There is an alternate position; it's forward and up a bit, under the passenger side exhaust manifold. The 3.4 when used in the Camaro had the sensor there, and I'd expect it's because of interference with the passenger-side starter. There should be a pipe plug up there, that goes directly into the block's water jacket.

If you were to swap the position of the sensor to the forward location, you'd need to drain the coolant down at least below that level. I'd use some non-hardening gasket dressing or liquid Teflon sealer on the threads of the sensor. It'll still make a good-enough ground connection to the block.

I've attached a pic that's useful for ZuZu 3.4 swappers, but it clearly shows the 2 knock sensor positions.
Note that the motor mount bolt pads info is just applicable to ZuZu swappers. I'd imagine in an S10, all (3) of the motor mount threaded pads line up to the stock mount.

Hope that helps............ed

Vehicle Motor vehicle Automotive tire Bumper Automotive exterior
See less See more
Well dang ok i’ll have to assess the situation and i’ll let you know what I do. Thanks
Do you know what the thread on that would be so I can go buy a plug for it? and btw what is that plug-in right next to that knock sensor? It has nothing plugged into it too.
1 - 20 of 37 Posts