I have a 1987 Chevy S10 Blazer with the 2.8L V6 and a 5 speed manual trans. I just changed the clutch a couple of weeks ago. The Blazer ran great for about 4 days and then all of a sudden stopped running as I was going down the road. I noticed there wasn't any fuel going to the TBI so I changed the Fuel pump, sending unit, and fuel pump relay. Still wouldn't start but turned over great. I wound up hot wiring the fuel pump to a manual switch and it starts and runs. I do not have headlights, horn, blower motor, and the radio doesn't keep a memory.
I did some research and from other posts with similar problems suggested the it is the oil pressure switch, so I just changed it and still the same problems. I did notice however that it seems like there is two oil pressure switches? There appears to be a 2 pronged silver one and below that is a 3 pronged bigger black one. Which one should I have changed or what is the world is the problem?
I would like to get this fixed so that I can drive at night and see the dash and use the A/C. Any help or ideas?
I don't have a lot of money to keep throwing at the darn thing.

 

You are right on there being 2 oil pressure switches, both will be next to eachother. If you replaced one, try replacing the other, they are only like 10-20 bucks. I am not too familiar with the oil pressure switches. I will do some research on this problem and see what I am able to come up with. In the mean time, it would not hurt to try replacing the other oil pressure switch.

What did you have to disconnect when you replaced the clutch (electrical wise?)

 

The only thing that I disconnected for wire and plugs I put them exactly back in the right spots including the grounds.
I checked the Ignition control module and had it checked and it is good. I replaced the cap and rotor while I was at it because they were horrible and needed to be replaced anyways.
I still have no headlights, horn, or anything. I can get it running by having the fuel pump on a hot switch but it will not start until the oil pressure gauge reads 20.
I ordered the second oil pressure switch that has 3 prongs on it and I will try that tomorrow when it comes in. Also by the way, the second switch costs $53.00.
Oh well, I am going to try that. Is there any other ideas why I don't have lights or anything?

 

53 bucks? where did you order it from, I would say you should have gotten it from rock auto, but since time is probably an issue and you want to get it running.

 

have you checked any fuses? Have you tested for power and ground at locations throughout the vehicle to narrow down whether it's in a certain region of the truck or if it's just a dead circuit?

 

That would be a good thing to check as well, is the fuses. If they have not already, that would have been the first thing I would have checked.

 

I have tested all the fuses and they are all not blown. I pulled each one out to make sure also. I am currently looking for blown wires and I have already checked all the grounds and they are ok.
I think that it may be a short or a shorted out wire somewhere. I just have to find it. YeeHaw! LOL

 

Electrical problems are the worst man, I am sorry. try to find something that all the things have in common, and start there possibly. I have a gm service manual for 82 s series, I will search it tomorrow, and see what I am able to find. There really is not a HUGE difference between 82 and 87, would give something to start with.

 

I agree that the electrical problems that I have with this blazer is really making me angry. I am almost to the point of just bringing it to the junk yard and cutting my losses. I probably won't because I have no money for a new ride and just keep limping this one along. I still have to start the blazer with manually switched fuel pump, cranking it over until the oil pressure gauge is up, and not being able to restart it after it is warm. It will only restart once the engine is cooled down. (Would that be some other sensor that I am missing?)
I have checked wires, followed wires, etc. I am on my way shortly to buy an OHM meter and retest.
Now the latest thing besides the electrical is something with my NEW clutch isn't working right. When I push the clutch in, it makes a clicking noise. That will be next on my long list of crap to fix.
No wonder I was able to buy this blazer for only $400. lol

 

I have posted some comments before about the electrical problems that I have been having with my 87 S10 Blazer 2.8L. The major problem that I having is that my truck will only start with my fuel pump hot-wired and cranking it over until my check engine light and my oil pressure come on. If I want to try and start my truck after it has been running a while, forget about it. I have to wait at least an hour and a half for the engine to cool down before it will restart.
I have changed both oil pressure switches, fuel relay, headlight relay, fuel pump, fuel pump sender, and checked all the fuses on the darn thing. My radio does not keep a memory, my headlights don't come on, my cig lighter doesn't work, all until the check engine light comes on and the truck starts. My power windows don't work unless I hot wire two wires right from my battery, then they will go up or down, depending on which way I touch the wires to the battery.
The only thing that I have not checked or changed is the ECM. I have looked all over the blazer for it where it is supposed to be, and still cannot find the darn thing.
I am in some serious need of some advise or something. Anyone have any ideas? The only thing that has changed before this started happening is my clutch. When I re-installed the clutch and trans, I made sure that all wires were hooked back up and grounds put back on in the correct spots. I know this because after I got done putting the new clutch in, I drove it for a week before all this electrical crap starting happening.
PLEASE HELP!!!!!!