Mysterious self healing car

engines
buick
lesabre

#1

why is it my car is fine when i take it to

the mechanic, but when I am on my mail route the car idles down and cuts off. It

even cut off while in motion a few times.

The mechanics say for the computer to tell

them what is wrong the car has to be doing what I say its doing for them to diagnose

the problem. What can I do to help diagnose

my problem? If I pad the accelerator while

it is in this mysterious shut down it stays

running. It shuts down before I can put it

in gear. desperately confused by mystery shutdown.


#2

Make, model, year???


#3

The mysterious self healing car is a 2000 Buick LeSabre with 130,000 miles powered by a 3.8 ltr V6.

jrh


#4

My guess is a fuel delivery issue. Possibly fuel pump or regulator.
There may save been a recall on the fuel pressure regulator, if so see if the recall was performed.


#5

My guess, especially if you’re in an ethanol state, is that you’re experiencing vapor lock. Doing all the drive-then-stop with a mail route gets everything really hot in the engine compartment, and if your fuel pressure is marginal from a weakening fuel pump or a partially plugged filter, even a newer fuel injected car can vapor-lock.

If you haven’t had the fuel filter changed lately, do it now. There’s a good chance that’ll resolve the issue.