I have a 1990 s10 4x4 blazer 4.3L vin (Z) that is overheating, idles rough, and oil pressure reads real low sometimes and then normal.

Overheating I have replace thermostat thinking that it was stuck but no go. My blazer gets hot fast at a cold start when idling and is really hot when on highway doing 60 mph at about 240 F i would say roughly.

My blazer seems to be missing? When I start it I have to pump the gas and it is TBI, which I shouldn't have to right? and the high idle is good but then kicks down and feels like it is misfiring. What could be the cause?? Also don't know if its related to idle problem, but when I push the pedal to the floor it hesitates, so I ease off and then gets going, but slowly. Wants to stall at stop signs and redlights too??

Last thing I know of so far is that the oil pressure gauge is reading low and normal, but never high like past 70 psi. usually idles at 20, drives city at 40 and highway it just fluctuates up and down and then the check gauges comes on when at zero but I have oil in it? Is there a solution to this problem?

 

Not sure about the oil pressure, but overheating and running funky can be caused by a lean condition. Make sure you don't have any vacuum leaks and check your fuel pressure.

 

The oil pressure could be due to low oil. If your vehicle is running lean it will certainly burn the crap out of the oil. Check to see if the injectors are clogged.

 

I have checked the oil and it is full because i just did a change on it two weeks ago. Vaccum lines look ok and all hooked up but cant tell why its overheating still and idling rough. One injector is looking a little clogged and the other is misting great. I will add some lucas fuel treatment to see if that cleans that up. Thanks for the input and info though.

 

well on the overheating issue i thought i might update a little since know one will give more advice on this issue. I checked the fan clutch and changed it cause it was kinda loose and not tight. Found a vacuum valve that was capped on the intake manifold but have no idea where it runs to? Blaze is still shaking at lights and stop signs and still has no "go" when i floor it? anyone got any advice on any of these issues.. Thanks in advance.

 

Fixed one issue today and it was the first thing I should have done. I flushed my whole cooling system and drives at a little under 210 and never rises higher than that! Success is so sweet. I still have the oil pressure problem and rough idle though? Anything would be great to help me. thanks in advance again for any replies.