hi folks, i just had a short block put in a 85 s blazer 4x4 i bought for nothing last year. I runs just fine till i stomp on the gas pedal then it stammers and stumbles and i can smell fuel. i thought this was a catlytic problem and hit with a hammer one day and also played with the dist and vacuum lines any it ran great no hesitating just very responsive, so i was relieved. This lasted about 3 days and it all started again. I cut out the catilytic converter thinking this would be the cure, well it wasn't to my shock. I have changed the fuel filter and tonight i changed the distributor cap and rotor, still no help. Plugs are good.
This is a 2.8l v-6 that sat in a field for a number of years before i got it. I just dont know what else to do short of taking it to a shop. If it were the fuel pump would i smell fuel? Could it be the vacuum advance? Coil? Choke? please give me some idea's or feed back if this is a known problem with this model. Thank you and have a nice day.

Ps What gets me is it ran just fine, in fact great for like three days????

 

is this carb or tbi?

 

Sorry, it is a carburator thanks for your response

 

If it got better after you played with the vacuum lines, I would be inclined to think that it is a vacuum line problem. Seeing as how the vehicle is 23 years old, I would suggest you go through the vacuum system and replace all of the rubber lines. Just take your time, replacing them one at a time. You may need to get some "T"s and other assorted vacuum fittings to complete the job, but I suspect that you have some collapsed vacuum lines that are not allowing proper vacuum signal to possible the vacuum advance on the distributor or a carb reference for proper fuel delivery.

The carburetor on this engine can be a royal pain if it does not see what it needs to. I had an 85 S10 pickup that was like this.

 

I wil try that, think i will put a carb kit in it, sitting for 5 years can't be good on the float? could be plug or coil wires. Think it can be the muffler??? Bunch of crap was in the converter. Just wonder if it all didn't blow into the muffler. Why would it run fine for 3 days????????????AAAARGH. That is why i think it is something electrical, just don't know. Hoping some more people will chime in by this weekend for ideas.