This is my first post hope you guys could help me out because i need this beast on the road asap for school. Anyways my blazer had been sitting for 2 years in that time i would start it no problems then just the weekend i started it and drove it and it was running fine until i got back to the house and it just shut off. I had the carbuerator rebuilt and cleaned before it was spitting out alot of gas then once i replaced it the gas flow was good but the blazer would still start but then go out with a puttering noise .....im thinking it has something to do with the maf or something electricle a short because it would run strong before this ny advice would be greatly appreciated.

and if it is the maf how do i replace it ? is it as easy as replacing a fuse or wire?

 

You do not have a MAF sensor on your truck so you don't have to fret over that.

Is the timing correct? When was the last time a tune up was done (plugs, wires, cap, & rotor at a minimum)?

*Moving to Full Size K5 Tech* - 1st Gen Tech is for 1st generation s-series questions.

 

I havent had a tune up in a long time and the spark plugs havent been changed could that be the problem of it not staying running? the timing is ok its a strong engine the check engine light is on though.. i appreciate the advice tho ; )

 

OK if your 87 K5 Blazer has a carb, then its probably fuel pump, which my 87 K5 has a TBI, look on the back of your TBI for a vacuumn hose trace it to a rectangular box on the psgr side og the engine block unplug it, and see what happens, you may also try the coolant sensor on the front just unplug it< and see what happens

 

K5BeAst87, get your trouble codes. Might point you to the problem. You should be able to cycle the ignition switch (key) On->Off->On->Off->On and the engine light will blink. Three blinks followed by four blinks is code 34... It will flash all your codes.

My haynes says 13 or 34 indicates an error in the MAP circuit. It could cause your problems, but no need to replace it if it's working. I think you can test the voltage (google, perhaps...).

Inspect your vacuum lines & connectors, too, especially the one to the MAP sensor (the rectangular box)

Sounds like your timing may be slightly off. See if your distributor is bolted tight (could have moved on it's own, try to rotate it by hand). At least inspect your plugs, they might be past-due. Same with cap&rotor. I just pulled plugs where the bottom electrodes looked like thin needles.

I have symptoms similar to yours, and I *know* it's my timing. Just got my timing light in the mail .

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