Just changed the fuel pump and filter on my 93 Blazer 4.3 vortec. i still have a problem with starting. after sitting for a while starts and run's for a second or 2 then dies. Will not start again for a couple min. Any one have an idea as to what is wrong. Tried renting a fuel pressure gauge. Autozone in my area doesn't have any. Trying the shradder valve it looks like the pressure is a little low. Any help would be appreciated. Thank you in advance.

Mark

 

Get a scan at Autozone with a scan see what codes your throwing,It sounds like Fuel injectors

 

I'm getting an ERG code and a rich exahaust code 3-2 and 4-5.

 

Sounds like your EGR valve is hung open and causing the rich condition. If the EGR hangs open, then exhaust gases are allowed to recirculate into the intake. Burnt gases do not burn again and if the PCM isn't compensating, there will be too much fuel than the O2 in the cylinder can completely burn. This would be where I would start with a simple cleaning and reinstallation of the EGR valve with a new gasket.

But really... Why the need for an entirely new thread on the subject? I'll lock the other thread, but in the future, please keep related topics to a single post. This will keep things from being confused.

The thread in question: Starting problem fuel pump ??? will have a link back to this thread for replies.

 

I've gotten the EGR valve off. Any one have somewhat detailed dirrections on how to take it apart to clean it completely. It's a 93 4.3 W motor.

 

Best bet is to use some sensor safe carbon cleaner and a tooth brush to get the valve clean. You will want to make sure that you do not get any of the cleaner on the diaphram of the valve... Your EGR valve is vacuum actuated is it not?

 

1st thanks for all the answers up to now. I've gotten the EGR clean and can hear it working, I also took the sensor off the top of the phellum, and both sides look identical, not like the one in the fuel pressureregulator link in the diy section. The vehicle still doesn't want to stay running. starts and dies in anywhere between 4 sec. and 10 sec. If any one has any ideas I would greatly appreicate your imput. Thanks for all the help up to now.
Mark

 

Have u looked into the injectors? seems u are getting fuel but injectors could need replacing

 

Have you gone through all of the fuses in the fuse box? I was playing around with my underhood fuse box the other day and had forgotten that I had removed a fuse from the box... Went to start it back up and pull it into the garage and it would fire, then die.

 

What is your fuel pressure? Do you have spark? Do you have injector pulse? Hook up a fuel presure gauge, a spark tester, and have a test light handy with the proper adapters to test the injector wires. When the truck dies see what FP you have, see if you have spark, and check to see if the injector is flashing. Do this and let us know which of the three you don't have. Then we can let you know what the next step will be.