I have a 95 4wd chevy Blazer 4.3 W. I have had alot of troubles withcarbon build up. Everytime I get on the freeway it gets stuck open and runs like crap. I am in the process of cleaning out the carbon and installing a new gasket with a filter. Is there anyway toprevent the carbon from coming back? I was told buy a friend that I should run better gas but if I dont have to spend the extra money that would be great. The other problem I have is starting. I have replaced the fuel pump and filter. Then I looked at my fuel pump relay which is located in the glove box and noticed a copper glaze on the contacts. After cleaning the contacts it seemed to fix it, but shortly after that the problem came back. So again I checked the contacts and the were fine. Any suggestions on that would be great. The mileage is about 180,000. Thanks and hope to here from someone.

 

Welcome to the site.

I run 89 octane with 10% ethanol. The ethanol helps keep the engine clean. Ethanol cleans. In hte meantime, pull the intake off and clean it up good. Including the EGR and PVC. Carbon build up is normal over time, and with 180K you will have some.

 

I took the egr off and cleaned the ports as good as I could. Then installed a gasket with a built in screen and put on a new pcv valve. That still doesn't eliminated the carbon built up but runs better. I think I will pull the manifold off and clean it better. Do you think if I run a higher octan it will help with the hard starting? Just the other day I installed a new fuel filter and that did not work. I read on one of the threads to trun your key on and wait for 15 seconds and then start it. That sometimes works like 50 50. Other than the usual problems it has been a very good suv if you keep it in highways. Thanks a bunch for you advice and I will give that a try.