Spits and sputters

STEVE MAXFIELD

MEMBER
1983 JEEP CJ7
6 CYL
4WD
AUTOMATIC
82,000 MILES

I drove my vehicle about forty five minutes and it drove great until the forty five minutes of driving and it started spitting and sputtering like it might be starving for gas. Carburetor has recently rebuilt, so I assumed I might have trash in my fuel filter. So cheap enough I replaced after it cooled down I was about forty five minutes from home. I drove back home it ran great again (loving this vehicle I bought a few months ago) and about a mile before I got home it started doing it again. I did make it home. Please help! Thanks

1 Reply

STEVE W.

MECHANIC
13,413 POSTS

Hello and welcome to 2CarPros. Your description sounds like good old vapor lock. The engine heats up and the heat is transferred to the carburetor and fuel line. This causes the fuel in the fuel line and float bowl to heat up and it shuts off starving for gas because new fuel isn't getting into the carburetor. First thing to check is that the thermal isolator is installed between the carburetor and intake. It's a a thick plastic piece that helps stop heat transfer. Next check the fuel line routing, you want it away from any heat sources like the exhaust or close to the engine. Check the fuel pressure as well a weak pump can also cause this, on that engine you should have 4-5 psi at an idle and about a pint in thirty seconds.