1997 Buick Le Sabre Wont start when hot

Hello, I have a 1997 buick le sabre and I experience very hard hot starts. This is not new problem just became worst.Is started in sept 08 and I ignored, as the car running very good.Now the starting became hard almost no start sometimes. I was at a Buick dealer and they want to change fuel pump, sender,etc total $1330 parts and labor.
The car is starting good in the morning is drive nice no hesitation, but after you live-it for about 15-45 min is hard to start. If is stay more is start without probrems. I clean the injectors, new fuel filter,new spark plugs and wires new PCV valve . I change the air filter with K&N just a mount before start acting . It can be oil from filter?
I can't remember everything I done but the gas pressure I remember is droped 10 bar when is running.{50 bar}. I am ready to change the gas pump I bought Delphi but I want to try everything before.
Thank you

try your changing your coil packs first

They check them at the dealer.They say are ok.
Thank you

I had one that did exactly that. It was actually getting too hot while running, but not enough to turn on the warning light. Then when it sat, the engine compartment must have warmed up more, and then when I went to start it, it wouldnt fire at all till I sat some more. When it cooled enough, it took right off. I finally found that the radiator was nearly clogged. I replaced the radiator, and had no more problems.

Thank you, I will check the radiator. Never was overheated the gauge stay at normal from the day one. I change the coolant 2 years ago and i did flush the radiator, was rusty but again no overheating.
Thanks

I can't remember everything I done but the gas pressure I remember is droped 10 bar when is running.{50 bar}. I am ready to change the gas pump I bought Delphi but I want to try everything before.
Thank youCould you please clarify the fuel pressure drop; remember 1 bar = 14.5 psi; so therefore, "10 bar" would = 145 psi! :eek7:

You could have a fuel pressure regulator problem, so you need to check fuel pressure @ prime, idle & with the vacuum line disconnected for an accurate test. Let us know what the fuel pressure readings are (psig) if possible! :grinyes:

Sorry my bad. I will write exactly what the dealer give me.
Check over coil and spark .ok.Pressure test fuel system ,about 10 psi low when running. Duplicated no start condition and measured fuel pressure. Only 20 psi. Will need new fuel pup module,sending unit ,retaining ring and gasket.Will cost about $1330 parts and labor.
This is what they say about the car.Is a Buick dealer.
Thank you again

Sorry my bad. I will write exactly what the dealer give me.
Check over coil and spark .ok.Pressure test fuel system ,about 10 psi low when running. Duplicated no start condition and measured fuel pressure. Only 20 psi. Will need new fuel pup module,sending unit ,retaining ring and gasket.Will cost about $1330 parts and labor.
This is what they say about the car.Is a Buick dealer.
Thank you againLow fuel pressure does not necessarily mean that your fuel pump is bad, it could be the regulator. In fact, they had a recall on the 97 regulators! In addition, the fuel pump & all parts are no more than 250-bucks and 1-hr labor to install. Get a second & third opinion from some independent shops, the dealer wants your money! :grinyes:

Thank you. I ordered already the fuel pressure regulator.I will change it just to be sure. Tomorow I will go to another shop and see what they say. I also clean the IAC valve and the EGR valve. Also when I change the PCV valve the MAP sensor was like broken in two pices.Top one and lower one. Is this how is need to be or is broken?
Thanks

Today I change fuel pump .Is starting good no more problems with starting. At idle, though, sometimes stalling. I think it is the MAP sensor.
I will change that next week. I keep you posted.
Thank you guys, you are great. By the way,total was just little under $400, parts and labor.
Liviu