2000 Blazer V6 122,000 miles. Turn the key and starts quickly every time and idles smooth. In park if I push on gas slow the tach will go all the way up. In park if I push on gas quickly it will hesitate, buck and backfire at about 3000, if I let off the gas some it will stop cutting out. I would take to a garage but it does not have enough power for the hills I must drive. It left me stuck on a hill already. I have changed plugs, cap and rotor. Tbs checked out ok. Put sea foam in but still have not been able to get fuel filter off for replacement but I will. Have not done fuel pressure test because I don’t have a gage and don’t think I can drive to get one, but if I must I must. It does not put out any codes.Appreciate any ideas.

 

Got to get the fuel pressure checked first and foremost if it's not throwing any codes. can't do much else till we see whats happening with the fuel system.

 

Thanks for the come back. Did a pressure test at service port. 60 pounds leak down at 55 after 20 minutes. Tested Coil, TPS, new air filter and new Plugs( lots of fun). Still same problem. Thanks again

 

Ok ,next you should do the Max Outlet Pressure test on the fuel pump. You do this at the outlet port of the fuel filter. It should show 73 too 108 PSI and have very little leak down. If it does have leak down then either the return check valve is bad or the pump is not able to provide constant consistent fuel pressure to the engine and a good regulator will not show this problem.

 

im having similar problem with my 2000 blazer backfireing into trottlebody but only does it for a few min affter a few min it piucs up and runs fine untill i stop and let idle for a few min then it starts choffing all over again what the hell is going on still not throwing any codes eigther

 

new plugs plug wires cap and rotor new fuel pump new dist. new crank sensor new fuel reg

 

Pappy you will need to do the Crank sensor re-learn on yours since it was replaced. this will cause issues if not done correctly and must be done on a scanner that can perform the task. Cheap scanners cannot do it.

 

so any suggestions where to go
?

 

i had don brown chevy do the relearn now my problem is the shock on passenger side came loose and jumped up and cut 5 wires i repaired wire and had to replace two o2 sensors now my problem is it starts perfect but doesn't want to move acts like and old carb with an accelerator pump problem untill it desisdes to move a couple of min after you try to take off then it runs perfect untill next time i turn te key off
any ideas