after spending days reading this forum and others, I am now posting. My 1995 chevy s-10 blazer will not accelerate. It started when the fuel pump quite working. I did general trouble shooting and replaced the fuel pump. After it was replaced she fired on the first try. I drove it about 2 miles and she has acted up ever since. I have good fuel pressure with no leak down, no leak on the spider injectors. Have recently done a tune up about 5k miles before the fuel pump failure. The blazer will fire up every time i try without hesitation, once the accelerator is pressed it cuts in and out. I have double checked all work that has been done

Part in last few thousand miles:

New intake set
oil pressure sensor
egr valve
plugs, wires, cap, rotor
fuel pump
fuel filter
muffler

when idling it runs really smooth. Once i start giving it gas it cuts in and out after a couple minutes it throws the code p0131. O2 sensor code. once the code is cleared and the vehicle is started again the code does not come back if i only let it idle. I do not want to throw parts at this problem and have spent several hours doing trouble shooting. I really do not know where to go Any help would be greatly appriciated.

 

let the truck get to operating temp when its dark out and see if your cat converter is glowing

 

also try unplugging the maf sensor and see if it helps. If it does then it just needs cleaned. I believe the 95 had one...lol

Nevermind, the 95 does not have a maf sensor. The next items I would check would be the throttle position sensor and the MAP sensor.

 

X2 on that

You could also try taking out the O2 sensor that is upstream from the cat and see if that helps. It will be a little loud but if the cat is clogged it will run better.

 

i checked the signal to the signal to the map sensor but i do not know how to check the functionality of it with what i have. I will check the cat problem tonight by removing the 02 sensor. The tps appears to working as well. thanks for teh info will try it.

 

From here:
MAP Sensors and how they work
I dont have time to put scanner on my Brava to check this but though it's for an 80's GM may still be true:

 

alright, i beat on the cat and there is a light rattle. Pulled the upstream o2 and it was loud but i was able to give it throttle. At the same time the idle went to crap and I had to keep it running. Once the engine got to operating temp it stalled and went into a no start. No codes showing. Needless to say the symtoms switched on me and I really do not know where to with the problem now.

 

Hmm if there was a rattle then that would lead me to believe its falling apart and therefor clogged. As far as the crappy idle and stalling goes, i dont think thats right.. or at least i dont think other people had that problem when they did that test. could be wrong tho.

But after it got warmed up did you look at the cat to see if it was glowing? if you have a way to take its temperature it shouldnt be anywhere over 300* or even about 270*

 

That's either too low or too subjective.
Therefore the only way to measure accurately is to stick a temp probe in the after-cat sensor bung.
Unless it glows, then it is way too hot.
And DONT beat on a cat. The way to test for rattle is to slap the pipe right next to it,, hard. Make sure it isnt the shield rattling

 

this is really confusing me. i have inconsistent symtoms. when at op temp the cat does not glow. hmmm