chug at idle & while driving after being warmed up/ driven a longtime

[jongreene]

After driving for probably about a half hour straight my car will do a little hiccup type deal, there is no change in idle, not really a power loss either, just kind of a chug.
also at idle you can hear this little chug, and the exhaust actually puffs out more air during this "chug". If you put your head under the car it sounds like its about in the middle, pretty much right under the driver seat. The car runs super rich,you can smell the gas..... i have a walbro 255 but not an AFPR yet, i have no cat either. Could it be that all the unburnt fuel is somewhat reigniting and causing this "chug"?...or is it just that i need and AFPR?...help please

 

[jongreene]

anyone?

 

[kronus]

Well, since you have no cat, there would be no place "right under the car" that would be hott enough to reignite the extra fuel. And if you're runnign pig rich, then it could possibly be a slight "bog" in your engine. You may want to check your o2 sensor and pull your codes. When those go bad, the ecu adds extra fuel to counteract any possible lean condition.

 

[jongreene]

if its an o2 going bad how come the symptoms are only after being run a while? i could be wrong but i just figured if it was the o2 the problems would never hide themselves

 

[ltvarney]

Jongreene, did you ever find the fix for this? I noticed mine doing this last fall before I parked it for the winter. It sounds like our setups are about the same, as far as the Walbro and test pipe. I do have an AFPR on order, which I hope will address this issue and which I will need anyway to support the Walbro 255. I didn't have a chance to check my plugs for fouling because it was so freaking cold out, but I'm guessing that is what causes this.