[Unknown User]

What is the best determination of when a fuel pump is going bad? When the car is running it behaves fine, but I have trouble starting it. I have to try 3 or 4 times and have to pump the gas. This should not be with a 1981 fuel injected engine. Any hints would be extremely welcome.

 

[Unknown User]

> What is the best determination of when a
> fuel pump is going bad? When the car is
> running it behaves fine, but I have trouble
> starting it. I have to try 3 or 4 times and
> have to pump the gas. This should not be
> with a 1981 fuel injected engine. Any hints
> would be extremely welcome.

To check the fuel pump, you could use a fuel pressure guage to see if the pump is providing adequate pressure. But I don't think the fuel pump is the problem if it runs fine after starting. Does the pump come on for a few seconds when the ignition is turned on?

 

[Don]

> What is the best determination of when a
> fuel pump is going bad? When the car is
> running it behaves fine, but I have trouble
> starting it. I have to try 3 or 4 times and
> have to pump the gas. This should not be
> with a 1981 fuel injected engine. Any hints
> would be extremely welcome.

Your FI system is a pressurized system. When you shut your car down there should be pressure maintained in the system even if it sits overnight. My guess would be that your system is leaking pressure somewhere in the system and that is why it takes so long to start. I would pressure test the system first to see if that's what is happening. You could have an injector that is not properly sealing (either FI or cold start) or possibly the check valve (sorry don't have my shop manual handy) located near the fuel pump. Sounds like your fuel pump is working if you can get it to start eventually. Good luck!

 

[Unknown User]

> I agree with the idea that the fuel pump is ok. I recently had all 6 injectors replaced. I guess the first place to look is the cold start valve and connections to the thermotine switch and other temperature sensors. Can anyone venture a guess as to what would be the most probable cause? I will also check all my lines in case of a slight leak in gas or vacuum.