'91 Fuel line problem?

Hi all, I have a 91 Park Avenue. It idles and runs great until the engine reaches running temp. At this point it starts to sputter like its running out of gas. The more I push on the pedal the less the car will accelerate. I sit and let the car cool down and it will run great again until the engine is at running temp (i.e. 200 on the meter). Any ideas would be much appreciated.

You have a temperature-related issue then. Generally, the crank sensor and coils are the most common parts to fail at operating temps. Also, neither of them (generally) throw a trouble code.

Is the SES light on?

Have you changed your fuel filter?

Sounds like a gradual build up until it just can flow gas anymore. Let it settle and drain back some and you'll get a few minutes of gas flow til it clogs back up.

Your coils are for sure heating up to operating temperature and they are starting to phase out. not throwing off the correct spark to make the injectors happy, and thus your engine is not firing correctly. start by evaluating the exterior of the coil packs. Generally on the 3800 there is 3 of them together. look for green goo oozing out of them. From that point, you can just replace them either way. Green goo means they are definatly bad, however if there isnt any signs of that, you can just replace them anyways. also, try some fuel injector cleaner, " it works"