ok so my mom has a 1993 gmc jimmy 4x4 with the 4.3 vortec v6. all stock and unless you clean out the egr every few weeks it gets stuck open and starts backfiring like crazy and trying to die. if you go a few weeks without cleaning it out you can get pea sized pieces of coal out of it. any idea how to fix this or whats wrong with it???

 

Hmmm... Sounds kinda bizarre. I don't have a real answer. But since the EGR valve usually just has fumes going through it coming out of the upper intake manifold, there must be some real crud getting into the manifold. What's causing that is hard to guess without more info.

 

it stopped for a while after i ran a can of seafoam through it but it started back, and these are HUGE chunks of carbon. i told her it had to be something else but she wont let me take the intake manifold off to look lol >_<

p.s. its not throwing any codes at all

 

If no one else here knows an answer for you, you may want to try our sister forum site Chevrolet Forum. It should be the same as the Chevy Blazer.

Link ---> www.ChevroletForum.com