badmix
1/2 ton status
Specs on my truck 84 K5, 305cid 125k miles, 700r, Holley 570cfm carb, mallory dist. heddman headers that need replacing.
Ok, im going to explain this the best that I can. For the last week my Blazer has been acting funny/odd. It runs "rough" at Idle and especially when you put it in drive. My tach reads 750rpm while in drive and 800ish in park. My vacuum gauge reads 18hg in park and 15ish in drive.
Both the tach and the vacuum gauge are holding a steady reading, they arent bouncing or moving or surging. There is no popping sound, no miss, no hesitation but when I put the truck in Drive the whole thing shakes, but the tach and vacuum are holding steady.
I have no idea where to look. Could be the carb needs adjusted? Motor mounts? Im not sure where to start, where its a mechanical issue (carb , timing, etc) or Physical issue (motor mounts, etc).
When Im driving down the road the truck runs great, no miss or hesitation, infact it runs really well. It starts right up and comes off the choke when its suppose to.
Im just not sure what kind of issue im looking at.
Thanks in advance.
***EDIT/UPDATE***
Well, hopefully someone can learn from this. Ended up being just a vacuum line. It was the line that goes behind the carb and into the intake manifold. Was split and 1/2 falling off. Replaced it and most of the other lines and truck runs like a top. And this is why I keep extra hoses and lines around.
Ok, im going to explain this the best that I can. For the last week my Blazer has been acting funny/odd. It runs "rough" at Idle and especially when you put it in drive. My tach reads 750rpm while in drive and 800ish in park. My vacuum gauge reads 18hg in park and 15ish in drive.
Both the tach and the vacuum gauge are holding a steady reading, they arent bouncing or moving or surging. There is no popping sound, no miss, no hesitation but when I put the truck in Drive the whole thing shakes, but the tach and vacuum are holding steady.
I have no idea where to look. Could be the carb needs adjusted? Motor mounts? Im not sure where to start, where its a mechanical issue (carb , timing, etc) or Physical issue (motor mounts, etc).
When Im driving down the road the truck runs great, no miss or hesitation, infact it runs really well. It starts right up and comes off the choke when its suppose to.
Im just not sure what kind of issue im looking at.
Thanks in advance.
***EDIT/UPDATE***
Well, hopefully someone can learn from this. Ended up being just a vacuum line. It was the line that goes behind the carb and into the intake manifold. Was split and 1/2 falling off. Replaced it and most of the other lines and truck runs like a top. And this is why I keep extra hoses and lines around.
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