hey guys i have an 89 c1500 with the 4.3 im having motor problems i believe. It will start and run for a while and sound fine other than not very responsive with the pedal but when i shirt it into gear and let off the brake its sputters and stalls out and then wont start but if i leave it sit and come back an hour or so later it will start and then do the same thing any suggestions or help i need to get this thing running....