Astro throttle body - what is happening here?

Messages
285
Location
Vancouver, BC
My 1994 Chevrolet Astro seems to have a throttle body leak that looks pretty nasty. I am not mechanically adept enough to understand exactly what is causing what looks like a crust of carbon on the throttle body - hoping someone here will weigh in! I believe it could be related to an ongoing vacuum leak on the vacuum hose connecting to the tb - the original pcv elbow is no longer available from GM and a mechanic tried fixing it using a piece of fuel hose in stead - it worked for a while, but it is back to getting severely flooded and wanting to stall when coming to a slow down at intersections, etc. Do you guys thing that "carbon crust" is related - leakage caused be repated flooding? What harm has this possibly done? How do I go about getting it fixed?
 
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Messages
767
Location
South Florida
when was the last time you had the whole assembly apart, ie the round "can" that sits on top of the body itself...and the upper and lower gaskets. they look like they havent been apart in a long time?? over time, i have noticed that the lower gasket on mine starts to get gummy and almost dissolved by the gasoline vapours....mine is ready for a change. I recently had to source an old rubber hose from the PCV system, my dealer didnt have it in stock but found another dealer in the country that did...all of the dealer should be able to do such a search. also, in the HELP section of parts in my local AAP and autozone, thet have the elbow hoses for the PCV systems that look close to being identical...just ideas for you??..
 
Messages
19,479
Location
Chicago Area
You should clean your TB thoroughly, and also any idle air control device. Good fuel line is great for vacuum lines, but you often have to loop it so it doesn't kink and restrict flow. so go fix this and any other vacuum leaks you discover.
 

sr17

Thread starter
Messages
285
Location
Vancouver, BC
Much appreciate the input! I don't think the tb has ever been cleaned. I will have to get this looked after. Wish I could do it myself, but I am not the most experienced at these things, and access is a pain in these vans.
 

sr17

Thread starter
Messages
285
Location
Vancouver, BC
Van is in the shop. Turns out that the issues are caused by a faulty intake manifold gasket - second time in less than 2 years.
 
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