Rough Idle

[cwilson jr]

well i recently purchased an 85 K10 with a 350.  it ran fine for weeks and after normal driving today it stalled on me, started it up, (which it now also takes longer to start), and now it misses horribly and stalls if i don't keep gas on it at stoplights, it still runs pretty good while cruising except there seems to be a dead spot when you first press the gas and the motor bucks out of nowhere sometimes while having the gas held down when driving, but while idiling and in park constantly misses and wants to cut out if i don't give it gas.  and will eventually, even while fully warmed up.  also i now have strong gas fumes that i didnt have before, so i know i'm getting the fuel, could this be in the distributor.  any help would greatly be appreciated.

Edited by: cwilson jr at: 4/24/06 10:22 pm

[Lt.Del]

Could be many things. I'd first check plug wires. Check plugs for fouling.

If that checks out, cap, coil, rotor.

Check for vacuum leaks.  Carefully take some wd40 and spray around engine.  If idle ever increases as you do that, you found a vacuum leak.  Check all of your vacuum lines...kinda sounds like one popped off or something.

SgtDel  

[Z28 c10]

BIG 10-4 on Andy's RE. it sounds like you've definetely popped a plug wire or fouled a plug. If all the wires are still on the plugs and you don't want to jump directly into a full tune up, just listen REALLY close for a tapping sound, it will sound just a little quieter than valve rattle. If you hear a tapping, than you've got a plug wire breaking down. If not, change your plugs AND wires, if they haven't been done in a while.

 JayTater

 Z28 C10  

[DnStClr]

I could be off base,but with the strong fuel odor, I'd be pulling the air cleaner off and looking for a choke or float problem at the carburetor. I don't quite follow the logic of bad spark plug wires causing a fuel odor. If a plug isn't firing, the unburned fuel would be exhausted and probably cause a backfire, no?

[DnStClr]

Oh, BTW cwilson jr- welcome to the site!

[Lt.Del]

Quote:and now it misses horribly and stalls if i don't keep gas on it at stoplights,

This sounds like an electrical/spark problem, however,

Quote:it still runs pretty good while cruising except there seems to be a dead spot when you first press the gas and the motor bucks

This sounds like a choke/carb problem.  I agree Don, if the smell is there, I would look at a choke adjustment.  I also would strongly suggest vacuum leak as mentioned before.

SgtDel
 

[cwilson jr]

thanks for all the help guys, haven't got around to troubleshhoting it yet, but that's just it at the moment its back to running fine at least on the idiling, still bucks/misses while driving occasionally but minor, also i did notice the orange choke light was on for a few seconds when the majority of this was happening, it never lit up before  and hasn't since.  again thanks for all the input and keep it comin'.

[DnStClr]

One other thing to keep in mind, if the carb is a Rochester Quadrajet- there's an accelerator pump in the carb and it's function is to control gas volume as the truck switches from idle to power, so the engine doesn't bog as you give it the pedal. They do go bad, and it's another possible cause of your trouble.