I performed a diagnostic on my 1995 Chevy S-10 blazer 4.3L Vortec and it said:

P0401 EGR Flow Insufficient.

I replaced the EGR valve and it is still idling heavy(RPM gage bouncing).



Any suggestion as to what I try next?

 

i have the same problem i cleaned the egr valve and passage and it still will not go away. anybody know what else could be wrong?

 

Wow... Old thread.

Want to fill us in on what it is you are driving Z28Justin?? Do you get this same code? Have you cleaned far back on both sides of the EGR passage? It could be restricted by carbon further in the intake or head.

 

yea sorry i didnt wanna start a new thred when there was already one. i have a 95 blazer 4x4 4.3 vortec, i pulled the egr off and soaked it and used fi cleaner and compressed air to clean as far as i could in the mani, put it back together with a new gasket (with the carbon screen) and 3 days later the p0401 code came back up. so far i have done cap rotor plugs wires 02sensors and new cat. but cant seem to get it to idle smooth.

 

The P0401 may not be causing the poor idle. Insufficient flow would be more in the form of a problem with the EGR supply pipes. You may need to use a long pipe cleaner to clean these tubes out. If there is a large restriction in one of these pipes (typically the supply pipe from the exhaust), then it can trigger this code.

 

i think im gonna buy a new egr valve, i have something that might work that i use to clean my paint guns to clean the manifoild. i hope that fixs it, is carbon build up really such a problem in these motors?

 

My 95 went through about a two year period, where I had to have the EGR cleaned, about every six months. It eventually stopped(for no reason), and I drove it 3-4 more years, without it ever happening again.

 

my 95 is doing the same thing but it also dose it when im driveing and i had the egr replaced with the screen filter and the intire motor vacum cleand at a local shop im confused as i can be about it lmao

 

i put in a new tps and it smoothed it out alittle bit but didnt fix it.