AMC Eagle Den Forum

The Mighty 258 => Fuel Systems. => Topic started by: amceagledude on May 10, 2011, 11:45:19 PM

Title: sputtering when step on gas pedal from stop sign
Post by: amceagledude on May 10, 2011, 11:45:19 PM
this happens when i take off from a stop sign or just giving it a little gas and stay under 20mph.  it doesnt do it untill the car has been running for about 20 minutes.  i had the carb rebuilt about 6 months ago. i had a place use a timing gun and that didn't work. i also have been slightly been advancing the distributer cap a little each day while its warmed up as well and it still wants to do this sputtering thing! should i just take it to the shop because the carb has a year warranty? thanks everyone
Title: Re: sputtering when step on gas pedal from stop sign
Post by: LaGuardia on May 11, 2011, 05:04:49 AM
I know little about timing (I'll have to learn, I know ;) ) but this thing doesn't seem timing related to me.

I'd bet on something related to fuel flow, so yes, the carb could be involved, but try with simple things. I'd check:

1) Fuel pump
2) Fuel filter
3) Fuel lines (as a last resource).

If it takes a lot of cranking before firing up in the morning (or after it has been sitting for a while), a weak gas pump could be the culprit.

For example, I experienced similar symptoms (ages to fire up and sputtering after stops) and I found out the diaphragm in the pump was cracked. This also led to gas mixing up with engine oil (check your dipstick if it smells like gas and the oil appears thinner than it should, you're there).

A clogged fuel filter could be another problem, and also some spark plug wire not firmly seated on the dist cap or plug sometimes might have such effects.

In the end, start with the simpler things and step up in complexity. The rebuilt carb is the last thing to investigate, and if everything else turns out to be OK, then you're going to claim your warranty with confidence...
Title: Re: sputtering when step on gas pedal from stop sign
Post by: BenM on May 11, 2011, 09:52:43 AM
Check all of the above, then if it still has problems I would suspect some crud in the carb.

You can try the old jug of gas on the roof method to bypass the whole fuel system and check the carb, but make sure you have the pump run directly into the return line first.
Title: Re: sputtering when step on gas pedal from stop sign
Post by: thereverendbill on May 11, 2011, 12:45:22 PM
I had a simular problem with my wagon when I first got it .   What cured mine was putting a line in/line out fuel filter and just capping the return line.   I've put over 1000 miles on it since with no problems