I just bought an 01 blazer, had been sitting for over a year. The guy said he had replaced the tranny, transfercase and fuel pump when i bought it.

So I brought it home, on the way home it ran pretty well, but when you step on the gas more than about 15% it's like someone is cutting the air or fuel off. So I replaced the plugs, fuel filter and changed the battery. It starts right up, idles great, and if you barely step on the gas it accelerates smoothly without a hitch. But as soon as you come down on the gas anymore the rpm's dive.

I tried parking it and popping the hood, it idled great, so i'd open the t-body slightly and the rpms would climb to about 3000 to 3500, then i'd open it almost all the way and it would bog right out, and it almost sounded like it was back firing in the intake when the rpms came down in the sub 800 area.

Any suggestions?

 

Also on a side note, it threw a bunch of misfire codes (i'm guessing) so i tried to hook my code scanner up to the blazer and it doesn't even recognize that it's plugged in. I have no idea if this is even related to my problem, but i know it's the blazer and not my code scanner because i tried it on 2 other vehicles without any issues, but when you plug it into the blazer, it won't even recognize it's there.

 

Does it do it all the time? Or just when it's warmed up and up to temp?

 

look at the catalytic converter sounds plugged to me

 

Come to think of it yes, runs great with tons of power when first started, but after it gets up to temp, anything over a little crack of the throttle kills it. So that would be a plugged cat?

 

I don't know what it could be, but mine did something similar and it was my transmission. Take the pan off yours and replace the fluid. Fluid and a new filter in $45. At least you could rule it out and won't hurt it to look.

 

Pull hte tranny dipstick and smell it, burnt smell, fluid is toast and so is your tranny, however I dont think that is your problem.

A plugged CAT will work great until you reach a point where the exhaust cant pass through the CAT fast enough, at that point your engine bogs down. Speed isnt a factor or a indicator in this case, engine rpms are. Teh engine is a big air pump, higher rpms the more air it pumps.

Truck sat for a year, replace the distributor cap and rotor, especailly if your getting multiple ramdom misfire. Run a can of fuel injector cleaner through the next couple of tanks.

A plugged fuel filter and/or failing fuel pump will also give you the same bog down problem, however it wont trip a code. Puter doesnt monitor fuel pressure. You have to attach a fuel pressure gauge and watch it.

 

My wife's Envoy did the same thing where the code scanner would not recognize that it was plugged in, it turned out that the fuse for the cigarette lighter was blown....I'm not sure if that helps