EGR valve has alot of carbon build up

[lants83]

Alright, my car likes to not start unless i give it gas and not idol when i finally get it running and it is quite hard doing the idol myself, because i only of 2 legs. i use to run 93 octane like a naive motorhead, then i learned about the waste of money that was. then i heard that my car isnt made to run that so there was probably carbon built up inside my engine. well, i unbolted the 2 bolts that holds the EGR solonoid on and show alot of carbon. so i have been spraying carbon cleaner into it hoping it will fix the problem. but it seems to help for awhile then my car likes to stall out again. i know it is my EGR solonoid that is giving my trouble because i pulled the code with a snap-on scanner. So if any one has any sugestions, insults on my stupidity or pitty. please let me know, thanks

[zlightning]

First off if your car is a v6 which I am assuming it is then it is meant to run on 87 octane gas. The carbon build up is normal. To me it sounds as though you have a fuel problem. I would get the pressure on your fuel pump checked and your fuel filter. To further clean the egr, find the pipe that leads to the upper intake manifold, if you don't know it is the piece that the air intake leads to, then unbolt the hose from the intake and clean it.

[John_D.]

Well, no insults for you today... [img]smile.gif[/img] The high octane gas is a common misconception.

As far as suggestions, first, for diagnosis, especially since you scanned it, sounds like you're on the right track. If the egr valve is sticking open (which it will, if the pintle gets too much carbon built up on it where it slides back and forth through the bushing) then it will idle poorly, but still run fine if you mash the gas all the way down.

As far as fixing it, you could:
1. Replace the egr valve.
2. Keep cleaning it, but like you said, that often only works for a short time.
3. Bypass it. First, get it to close, then unhook the wire/vacuum to it, so it won't be able to open again. You may still get a light (I do on my '98), but it will idle and run correctly.