Skip the auto shop - Our mechanics make house calls

Q: Truck sputtering going uphill.

asked by on

My truck sputters when going uphill, and has died a few times because of a lack of fuel getting to the carburetor. It has a new mechanical fuel pump and fuel filter, custom fiberglass tanks under the fender on each side, and I have replaced both gas caps. The carburetor has also been replaced with a Holly 4-barrel. It seems like it could possibly be a vapor lock issue, but I am not really sure what is going on.

A: I would only be speculating on this problem...

I would only be speculating on this problem since you have altered the fuel tank system on the truck. I suspect that the fuel pump is getting starved of fuel and when you are going up a hill causes the pump to not be able to keep up with the amount of fuel needed to supply the carburetor with enough fuel. I would check the volume of fuel you are getting from the fuel pump and see if it meets the specifications of the pump. If it is too low then look at getting a high volume pump and even look at getting a low pressure electric pump to help keep fuel supplied to the mechanical pump. Put the electrical pump as close to the fuel tanks as possible. I would also recommend that you have a professional, certified mechanic take a look at it, such as one from YourMechanic.

Was this answer helpful?

Need advice from certified mechanic? Get help now!

Over 1000 mechanics are ready to answer your question.
The statements expressed above are only for informational purposes and should be independently verified. Please see our terms of service for more details

Ask a Mechanic
(100% Free)

Have a car question? Get free advice from our top-rated mechanics.

Ask A Mechanic
Over 10,000 questions answered!

Get an instant quote for your car

Our certified mechanics come to you ・Backed by 12-month, 12,000-mile guarantee・Save up to 30%

Get a quote

What others are asking

Q: Car starts fine, runs briefly, sputters and shuts off - 1994 Cadillac Fleetwood

Hi! Yes, I have a couple thoughts for you to hopefully get your Cadillac back to being a reliable driver. From what you've said so far, I agree that the distributor and the fuel pump are high probability suspects. Now...

Q: What does it mean if the Check Fuel Cap message is displayed?

A common misconception is that the only purpose of a fuel cap is for it to be a top for the fuel tank. It actually has many purposes and is a critical component of the evaporative emissions (EVAP) system. If...

Q: Passenger side brake light is not working - 1971 Volkswagen Super Beetle

It may just be chance that the other light quit working as well. Replace ALL of the brake light bulbs at the same time with the right bulbs and if they still do not work, suspect a problem in the...

Related articles

How Long Does a Distributor O Ring Last?
The distributor is part of the ignition system in your vehicle and its purpose is to route high voltage from the ignition coil to the spark plug. The spark plug then...
P0240 OBD-II Trouble Code: Turbocharger Boost Sensor B Circuit Range/Performance
P0240 code definition Turbocharger Boost Sensor B Circuit Range/Performance What the P0240 code means P0240 is an OBD-II generic code triggered when the Engine Control Module (ECM) detects the intake boost...
How to Avoid Back Pain in a Car
If you have back problems, sitting in a car for an extended period of time can be excruciating. Even without back problems, you could experience discomfort and soreness from...