I have a 92 S-10 Blazer 4.3L cpi 4x4.
I'm having a few problems with my blazer and was hoping you guys could help me out. My Blazer is a daily driver and I've done all the maintenance and repair on it ever since I bought it about 5 years ago.
My main repairs have been: Fuel inlet hoses, Intake manifold gasket, Fuel Filter, Fuel pump, TPS, MAP sensor, EGR Valve
Generally any time I notice the blazer operating irregularly it takes a long time before I get any trouble codes.

Okay here's what I've got happening:

1- My oil pressure usually reads 40 psi, but here lately it's been dropping to around 20 psi while driving and when I come to a complete stop I have no pressure at all and the oil check light starts flashing. There seems to be no effect on engine performance when this occurs and I probably wouldn't have even noticed it happening if it weren't for the check light catching my eye the other day.

2- I have replaced the TPS at least 3 times in the last 2 years. Occasionally the engine will seem very sluggish and take a lot of gas pedal to accelerate throughout the operating range. The engine doesn't feel like a "miss" but more like it's bogging down. The "bogging down" generally happens for about the first 5 seconds of acceleration.
I've had this problem for a while and it never occurs on a consistent basis. The only trouble code I've ever gotten was for the TPS.

I've had the second problem for a while now so I'm pretty confident that there's a good chance that both problems are unrelated. I saw a similar thread a while back and it was suggested to perform an oil and filter change which I plan on doing a.s.a.p.

Any suggestions would be extremely helpful, thanks guys.

 

Hook up a mechanical gauge to the oil pressure sending port and verify the pressure muy pronto.

 

Thanks for the suggestion man, I've got a manual gauge tracked down.
Now to get my hands on it I gotta wait out this snowstorm, thanks again.

 

I would also check for a pretty good oil leak at the sender.

 

Again thanks to everyone who responded to this topic.

So yesterday I locate the oil sending unit, which by the way is located underneath the distributor...and when I say underneath, I mean almost impossible to get to LOL
Anyway, the oil sending unit was leaking and obviously bad so I bought a new one and set to replace it. To make a long story short, I ended up taking a portable bandsaw and cut the handles down on a pair of channel-locks to make a tool small enough to get the old sending unit out and install the new one.
After that I took the blazer for a test drive and everything is back to normal, thanks a lot guys for all your suggestions I had absolutely no idea where to start troubleshooting this problem.
On a side note if you ever have to perform this repair make sure you have some large deep-well sockets at your disposal, I figure the socket needed to properly remove the factory sending unit to be about 1 3/16", which I did not have...
I also replaced the TPS as it was under lifetime warranty, only I'm am becoming concerned about the frequency of failure I have with that particular part.

Once again thanks a lot, I really appreciate this forum as it has helped me many times in the past with troubleshooting. Have a good one guys!

 

The original factory oil sending unit the electrical portion is larger than the body of the switch so it is impossible to get a socket over it. The replacements however are such that you can get a socket over the electrical section. The other difficulty is that the sending unit is mounted on an angle adapter so if the adapter turns and not the sending unit you can not get a 360 degree rotation without the sending unit hitting the firewall. I had the misfortune of snapping off the adapter flush with the block. But I was able to get a replacement from a junkyard and remove the piece from the block with an easy out.