hey i cant figure this out when im in rverse or goin slow from a stoplight the whoile truck shuddders and stalls mostly when i dont give it a ton of gas to get it not to stall it dosnt shift well unless i let off the gas and itll switch intpo the right gear so i think i got a vaccum thing in my transmission but could this make it shudder and stall when going slow?also when i stop and turn it off it shudders and makes a souind like it releasing a bunch of exhaust ..it pops kinda like a backfire befor it dies also..ive adjusted the carb done the timeing a bunch replaced some vaccum lines i just dont get it ..please help 78 k5

 

Check the ERG Valve

 

what is it and where is it

 

He means the EGR valve (The EGR valve helps your car more efficiently and completely burn fuel by recirculating a portion of your exhaust and running it through the combustion process again. This results in a cooler, more complete burn of the fuel which decreases you car's noxious emissions by prohibiting the formation of some harmful gases.), it should be located on the intake manifold. Here's a picture of it, EGR Valve for 78 K5

 

does that seem like the symptoms of a bad egr valve because those arent that cheap but if thats it then thats pretty easy

 

just block it off, unless you have emissions testing in your area.
I bought mine at advanced auto parts but you can get them just about anywere, or you can make your own

 

if i blocked it off how would i do that ..just so i cand see if thats the problem .then if it is ill go get a new one i dont know how to block it off though

 

im guessing my EGR valve is bolted straight to my maifold under my carb but theres a smaller similar lookin thing with a vaccum hose goin to it under my distributor but im guessin its the bigger one under the carb oh yeh its a 78 k5 350 whats the tourque on the egr valve?

 

to block off just unbolt and bolt on plate with new gasket, could not find the bolt torque specs on it but i just tighten it down. as for the vacuum line just block it off
egr+block+off+plate - JEGS High Performance

 

hey thanks for the link i didnt thing about jegs even though i get the catalog its 13-18 ft.lbs i foud out i finnally got my service manual back