When i first start my 95 lesabre it run really rough until its warm after its warm it idles real nice but if i give it too much throttle too fast it cuts out and loses power especially up hills.i just hadf it tuned up new fuel filter,plugs and wires etc. and problem still persists what could this be and also can i hook my 1995 lesabre 3800 up to a obd2 tester

SOURCE: buick lesabre nightmare

Need to get a scan tool and look at the data stream while it is running for alot more info.Also any trouble codes.Sounds like initially,the engine isn't getting any fuel.I would have a pressure gauge connected to the fuel rail on the engine,so i could monitor the fuel pressure while all this is going on.Items to look at on the data stream would be timing,what timing is the PCM commanding for the engine.Also,have you checked for continuos power feed to the coils during this no start condition,and fire at the plugs while cranking.You could possibly still have spark,but maybe it is extremely weak?I have seen bad ignition switches cause weird problems before too.Many things power up through the ignition switch,just a thought.Have also seen bad PCM's cause strange problems..38 volts is a little on the low side for GM.Usually see those at,at least .50 and up,and rise steadily while pressing the throttle,up to just under 5.0 volts.Potentiometer with 5 volt supply.Vacuum leak can be checked with engine running at a steady idle speed,spray brake cleaner all around the intake manifold and listen for engine speed change.

SOURCE: buick lesabre no start

Hi you have replaced allmost everything ,(try fuel pump relay)

SOURCE: rough idle

fuel filters rarley cause idle problems. i would look at the egr valve or possible vaccume leaks.

SOURCE: 1997 buick Lesabre studers when driving over 50

Sounds like what is called shutter changing to synthetic fluid fixed my 98 Lesabre

SOURCE: Lack of power on 2003 Buick Century

might have the transmision shift solenoid check