I have a horrible engine bog! When I go to accelerate from a stop light, throttle between 25%-50%, the engine bogs bad. When I put throttle at 100% and take off from a light there is no problem. Also when I am trying to pass some one on the highway I was punch it and there is about a second or two delay from when I push the peddle down to when the engine actually revs up. I cleaned EGR and MAF sensor about two months ago. It's a 2001 blazer 4.3, 164xxx miles, CAI. What could be the problem with the hesitation?

 

Try changing fuel filter,

 

are you running the air conditioner?? cause i know that pulls mine down pretty bad. the pully's on the 2000's take about 15 horses to turn so if you are turn off the a/c and try it.

 

have your tps tested.

 

It doesn't matter if AC is on or off it bogs either way. I'm having a hard time getting the fuel filter off so I'm taking to my uncle's shop tomorrow to see if one of the guys can give me a hand with it.


As in Throttle Position Senor? How Do I test that?

 

Ok finally changed the fuel filter today. What a job that was! A 5 min job took about an hour with my uncle who has over 25 years of experience under his belt. It runs a little better now but still kind of slow.

 

The TPS might be adjustable.. I don'T know about the Blazer or Jimmys, but on my V6 Explorer it is adjustable by releasing a screw and retightening when the sensor is in a position that allows it to reach optimal voltage (you measure it trhough a voltmeter). Once the voltage is between .95 to 1V, you are in tune. These trucks might be similar, but I have no insight on that.

 

TPS voltage should be roughly 0.5V at closed throttle and 4.5V at wide open throttle. If you monitor the output voltage to the PCM from the TPS sensor and move the throttle from closed to open, the voltage should take a smooth increase. You will have to test this with the key on so the PCM is delivering the 5V reference to the TPS sensor.

 

ok finally found my volt meter yesterday and I tested the voltage at the sensor, it measured .45v closed 4.31v wot. is this acceptable or is the sensor going bad? i also went to A.A. today for my s.e.s. and the two codes the guy pulled were P0410.

 

Those sound good. You should also check to make sure that the voltage never drops out while you go from closed to wide open throttle. It needs to be a smooth transition between those two voltage readings you gave.

Both codes were P0410? Check out the DIY section for the book explanation of P0410. This really should not cause a bog though.