How JustAnswer Works:
  • Ask an Expert
    Experts are full of valuable knowledge and are ready to help with any question. Credentials confirmed by a Fortune 500 verification firm.
  • Get a Professional Answer
    Via email, text message, or notification as you wait on our site.
    Ask follow up questions if you need to.
  • 100% Satisfaction Guarantee
    Rate the answer you receive.
Ask Canada fix Your Own Question
Canada fix
Canada fix, Owner/Technician
Category: Car
Satisfied Customers: 1632
Experience:  Trained in a Ford shop. Worked for the last 21 years as an independant. 19 of those in my own shop.
Type Your Car Question Here...
Canada fix is online now
A new question is answered every 9 seconds

Hi, Im writing because my car wont start. Its been having

This answer was rated:

Hi, I'm writing because my car won't start. It's been having issues for awhile. After driving it for anywhere from 15 minutes to 30 minutes, the car starts lurching as if gas is being supplied to the engine every couple seconds. During these episodes, the rpm's roll between 1000 and 2000, roughly jumping between the two. Acceleration is rough when this process starts and the car will eventually slow to barely 15 mph. It has a high idle and is rough to start, sometimes shaking the whole car. Once it is started though, it drives fine for about 15 minutes, though this time can vary. Today when I was driving home, the internal lights in the car started to dim and the car quickly died. I have a voltage meter in my car and saw the battery was in the red. I recently replaced the battery and the fuel pump. When a friend tried jumping the car, it started, but died as soon as we removed the cables. After a couple tries, we got it to stay running, and as I was close to home, I figured I'd try and get it there. It drove for about 1-2 minutes before a sound that sounded like a gunshot came from the rear of the car. This reminded me that occasionally there would be a clunking sound near the rear of the car as well, though I noticed it was diminished after I got the fuel pump replaced. The car is a 1977 Datsun 810 with 88,000 original miles on it. I also recently replaced the cap and rotor, thermostat, fuel filter, oil, and radiator cap. The oil appears clean and there isn't an unusual amount of exhaust. Any ideas what could be wrong and how much it might cost?
Good morning and welcome to Just Answer.

My name is XXXXX XXXXX I will try to assist you with your Datsun.

To begin you should address the low battery problem.
This may be affecting the performance of the engine as well as the low voltmeter.

The first thing to check for is a slipping belt on the alternator.
I am thinking because it is intermittant that this may be your issue.
The belt must be tight. The alternator, when under load takes a lot of energy to rotate.
If the belt is loose, the alternator cannot charge the battery.
If the belt is indeed tight, then check carefully the connections to the alternator for corrosion and verify they are tight.

Also make sure that the grounds are good to the engine and the body from the negative battery terminal. If there are poor grounds, this can also affect engine performance such as what you are experiencing.

I do believe most of your issues are electrical based.

Check that out and let me know if you need further assistance with your problem.
I'll help you along if I can.

Thank you kindly,
Customer: replied 4 years ago.

And this would also cause the car to lurch after it is driving for a while? Thank you for your time.


It's possible.
Without proper battery voltage being applied to the ignition it can cause all kinds of symptoms.
You need to address this in order to go further.
Because of the charging system problem it will be difficult to properly diagnose anything else. Voltage needs to be proper in order to correctly operate the fuel pump and ignition systems.

Let me know what you find out.

Thank you,
Canada fix and other Car Specialists are ready to help you