Like the title says, I have a 1982 Cutlass Supreme with a 4.3 v6 diesel engine. My dad has had the car for a long time and gave it to me a few years back. It has 73k miles on it, only really sees a few hundred miles a year. Recently it started running real rough and we cannot seem to get to the bottom of it.

The fuel gauge is broken so last year when I put it away I thought the tank was topped off..however it was not. So I am not sure i that has anything to do with the new issues. The car spontaneously will run and idle very rough, sometimes struggling to accelerate and other times just struggling to run at all. The majority of the time it runs fine and you wouldn't know there is an issue.

We changed the fuel filter thinking that may be the issue. Changed the air filter thinking maybe that might be causing it. Now I am really not sure where to go next. The injector pump was rebuilt years ago, and my father thinks it may be that...not sure if anyone on here had any thoughts. Sorry if my description of the issue is lacking, if I can provide any more details or answer any questions I would be more than happy to! I just want to get this thing back in tip top shape so I don't worry about being left stranded.

Thanks for the help!

 

Have you tried running off a fresh clean fuel source?

Pat

 

We actually drained the fuel out of it, and put in completely new fuel from a new station.

 

X2 on trying a fresh clean fuel source...with a diesel fuel injector cleaner mixed in.

Good luck!!!

 

Wasn't fast enough on the typing...

 

I can put in some fuel injector cleaner...any recommendations.

 

Let's start again! Take a clean fuel can, rig up a fuel line to the injection pump and see how it runs from there.

As far as fuel system cleaner, I would suggest a Stanadyne product:


I am trying to fully understand your original post. Now it runs rough intermittently?

Pat

 

It might be worth looking at the timing chain, if it's badly worn it might allow the pump timing to move about a little.
I understood if the fuel was kept clean the pumps were pretty reliable. But if it has been damaged through corrosion or dirty fuel then you have a problem I'm afraid.

Roger.

 

Good news is you have the best Olds diesel. How old is the fuel? A water fuel separator is a good idea as it should have been factory installed. The timing chain is pathetic on the diesel motors with no heavy duty upgrade.

 

Fuel was put in a couple months ago to try to solve the issue. We drained all the old fuel and started with new fresh fuel.

 

I am trying to fully understand your original post. Now it runs rough intermittently?

Pat[/QUOTE]

yes, sometimes I can drive it and it drives perfectly and doesn't have any issues. Other times, like the other day, I started it and it was idling and running extremely rough and thought it was going to die. Then I drove it for a bit and it started running better...it's confusing