Hey folks,
I am a tech at a small local garage and had a '95 Chevy Blazer VIN W 4.3L come in recently. When cold, the vehicle runs and drives perfectly, but when hot it hits a dead spot at wide open throttle where it spits sputters and sometimes the rpm's just drop. I have checked the MAP Sensor, Ignition Coil, and used my scanner to check TPS Voltage and %, MAP Sensor Voltage. I have checked fuel pressure, checked for vacuum leaks, shorts to ground, and every other thing I can think of. I need someone to point me in a new direction because I am stuck. Thanks!

 

I need some suggestions guys. Anything would be helpful, just throw your ideas my way, no matter how 'out of left field' they may be. I just need a new way of looking at this problem.

 

Kind of sounds like what mine is doing, but im having the problem at low rpm and all of the throttle.. Is it running warmer than usual? Does it give a low roar from the engine when this happen's 'if you continue to attempt to accelerate'?

 

No, Not running warmer than usual. Spoke with a tech from Chevy, they said change the fuel filter first, then if that doesn't work, it is probably the catalytic converter. so, we'll see what happens

 

Kool, I was thinking about maybe the converter. Thats why I was asking if it seems to be runnung hotter than normal. I dont know about a 95, but my 2000's fuel filter is latched on the frame, driver side, between the two doors.. if you have a 4 door that is. Good luck! let us know what it is..

 

Are you throwing any codes??

 

Nope, no codes. changed the fuel filter, no dice. changed the cat...no dice either. Gonna replace the coolant temp sensor for the computer and see if that does the trick. cross your fingers guys!

 

I was having a similar problem in my 01 2wd, would have a dead miss. I was changing the cap and rotor and found the distributor shaft had a lot of radial play. Swapped it out and it runs great for now. I also noticed it was making a crunching sound under the dist. cap.