From what I am reading here,, my 2000 Blazer,, 2 wd with only 87,000 miles,, 5 speed gear box,, my issues,, runs fairly good cold,, after warm up and go to a store ect,, starts but no power, hit the throttle and it will back fire through the intake,, after a few short minutes,, and pumping the pedal it will "come back to life" My f/p is 54 psi,, changed the fuel filter it help the running issue but the f/p stayed at 54 psi,, also my brake & ABS light is intermittent,, pops on while driving and shut the car off and at times after restart its gone,, and other times it is on at start up,, both front hub bearings have been replaced with new Timken bearings with new sensors built in,, So my next step is too replace the fuel pump with a delphi new pump from NAPA,, If I cant get this truck a little more dependable I will trade it in,, but hopefully I can get her going smooth shortly,, Thanks for all the help so far!! Matty man

 

Are there any stored codes from either the PCM or the ABS that might give direction for diagnosis?

 

If this is a 4.3L, 54psi is too low. Must be 60psi to 66psi, key on, engine off, fuel pump running, (there is no engine running fuel pressure spec). This thread will walk you through the diagnosis:


https://blazerforum.com/forum/tech-a...agnosis-23038/

 

Thanks for the replys,, no ABS codes using AZ to pull the codes and they say no,, only both O2 sensors showing lean,, my first step is too swap out the fuel pump,, I really like this truck,, so lets get started and the f/p in 2 weeks,, cant wait on that,,, Thanks matty man

 

The generic scan tools that are most commonly used at AZ are not capable of pulling ABS codes so I wouldn't use that as confirmation that there are no stored ABS codes.

Have you tested the MAP sensor? Cleaned the EGR & MAF sensors?

What were the specific codes that were present? Lean codes (P0171 & P0174 - forum search for "P0171+P0174") do not point to any one particular sensor as being the problem. Vacuum leaks are the most common cause of these codes, but low fuel pressure can also cause them speaking generically. Typically though, once the fuel pressure drops a bit, the engine just dies due to the pressure actuated poppet nozzle setup in these fuel systems. It typically won't get to the point of triggering a lean code because of this.

 

I have not tested the MAF,, I did clean it and it seemed to help,, I have not done anything to the EGR,, I will do a search on testing the MAF,, Thanks for the help!! Matty man

 

Give that EGR a good cleaning, certainly wont hurt.
But fuel pressure should def be a little higher.

 

The EGR will get cleaned when I do the pump in Mid October,, I will also look at the plugs and see what is in there,, the previous owner may of been the king of half a$$er`s,, thanks for the tips so far,, I will post when I start the pump swap out... matty man