1995 Blazer Clumps of carbon deposit chunks keep getting stuck in the egr valve the clumps make the valve stick and make the blazer run rough what causes the clumps of carbon and how can you fix it?

Answer 1

Visit an auto parts store and get yourself some SEA FOAM engine de carbonizer; old engines of all sorts get carbon build up it is normal fuel and air combusting cause the carbon.

another wayGo to your local auto parts store and ask for the egr valve gasket and screen made by temco. State year, make, model and engine size and code. The screen built into the gasket will catch the clumps and egr will not be a problem. Don't treat the symptoms, fix the problemThe carbon chunks are a problem that has plagued many 1995 owners. The carbon chunks are caused by unburnt fuel exiting the engine. The carbon chunks enter the EGR valve as it opens to allow exhaust gas into the combustion chambers. The gaskets with the screens will temporarily relieve the symptoms, but will trap the carbon chunks in the EGR ports of the enigine block, eventually causing them to clog and result in more repair work. It's much more effective to fix the cause of the unburnt fuel in the exuast. This rich condition can be caused by many things, such as faulty 02 sensors or the engine needing a tune up, however the most common cause is unmetered fuel leaking into the intake. From 1993 - 1995 these enigne used a central port injector (CPI), which is a single fuel injector mounted inside the intake with lines and poppet valves going to each cylinder. This system has two weaknesses, the internal fuel lines (called the "Nut kit" by GM) and the fuel pressure regulator. These two items commonly leak and cause unmetered fuel to leak down into the cylinders. It can even leak so bad that the fuel will leak past the pistons rings and into the crankcase oil, eventually causing catostrophic engine damage. Luckily these problems are easy to diagnose. You can pull the vortec cover and the IMT valve to try peeking through to see if they're leaking, but it's better to pull the upper plenum so that you can get the full view. The whole inside should be black, if it is leaking there will be clean spots from the fuel washing the inside. Clean spots on the driver side indicate a leaking nut kit. Clean spots on the passenger side indicate a leaking FPR. If one of them are leaking you can replace just the one that's leaking, but a lot of people just replace both so that thay don't have to worry about it.

GM has also issued a TSB regarding the EGR problems. It involves reprograming the computer to cylce the EGR valve at certain times to help prevent carbon buildup.