Hey i got a 99 sc2 and my egr valve keeps getting clogged. i had a chugging problem about a year ago didnt know what it was got a shop to look at it and they said my egr valve was clogged and they cleans it for 200 bucks...6 months after it happened again but then i new what was going on so i cleaned it with carb cleaner. Then i wen to niagara falls this weekend and it happened again but once again i new what was wrong and un clogged it in 10 mins and continued my trip. How can i fix this problem where it stops clogging every 6 motnhs??

Quick EGR Theory...


Exhaust Gas Recycling (EGR) serves one purpose and one purpose only.That purpose is to reduce Oxides of Nitrogen(NOx).Under normal combustion, Nitrogen(N2) Oxygen(O2) in the air and Hydrocarbons (HC) in the fuel combind into water(H2O) Carbon dioxide (CO2) and the Nitrogen remains unchanged.Under very hot combustion temperatures, the Nitrogen reacts with the other two byproducts and forms Nitrogen oxide (NO).After being released into the atmosphere, it picks up another Oxygen and becomes Nitrogen dioxide (NO2).In the presence of sunlight, it combines with other compounds like Hydrocarbons and forms Smog.Since exhaust gas is inert (very stable) it does not burn again.So by being introduced into the combustion chamber, it will lower combustion chamber temps enough so that the Nitrogen does not react with the other compounds and is passed unchanged out the tailpipe thus not contributing to smog.Now, since exhaust gas does not burn, it
does not exactly help with combustion.At higher RPMs, this really is not noticable, but at idle, the reintroduction of exhaust gas will cause a very rough idle and can cause stalling if too much is introduced into the combustion chamber.As the temperatures lower,some of the hydrocarbons form the gunk and deposits you have to clean out, so the bottom line is simply an issue you learn to live with (carry a spare)

thanks for the info, i did clean it out well and working good but isuppose it will happen again oh well easy fix..

Make sure you are cleaning the two ports where it connects to the engine.

This will likely continue to occur until you address the oil consumption issues you have.

How much do you burn between oil changes?

wow you nailed that one haha...i burn prolly 2 litters every 3-4 fill ups about 1400-1800km..could this be cause bye my sticky rings?

indeed the oil control rings get stuck (seize) and cease to sweep the cylinder walls as designed. Burning that much oil will result in a endless EGR fouling issue like the one you're in....

has any here got their sticky ring problem fix and how much do you think it would cost...i guess i should be working on this and savin some dough

Too much is how much it will cost unless you do it yourself....and if you do, you might as well do valves and valve guide seals while you're in there....oh, and maybe a water pump and timing chain.........

Not that it matters, but how many miles on the 99?

Hey guys my 96 Sc2 keeps failing etest under the NOx category. I replaced my egr valve and am going to try retest..could this have been my problem. It was gettig a high reading before so Im assuming this may be the prob. Any suggestions?? Anybody relate w/this?? Thnx.

answered your post in other section. Indeed EGR could be culprit, especially if you burn a lot of oil. However, still recommend ECTS sensor and connector replacement