I have a 97 olds 88. while driving sometimes the engine will just shut off. In rare cases the engine will quit and when i start it up again and give it gas it shuts down. after awhile it will be fine and drive great. do you think it is the fuel pressure regulator? I don't think it's a fuel pump cause it gets fuel. Seems like the pressure is not always there.

Will not crank how ? When you turn the key to the start position does the starter engage and spin the engine ? , A crank no start condition . Or nothing happens . A no crank - no start condition . I assume by your statement ( Had ignition control module tested ) That you have a crank no start condition . in which case have you tested input from the crank sensors to the ICM and PCM . What engine does your Old's have ? 3.8 L
Is there spark at the coil's ? Pull plug wires off of the same coil , have someone crank the engine over , Is there a spark jumping from one coil tower to the other ? If so , you don't have an ignition problem , fuel more then likely . Is your SECURITY light lit on the instrument cluster , if it has anti-theft .

Sounds more like a electrical issue, perhaps a bad computer. I had one case where the oil sending unit had a broken wire inside the insulation. When the car was cold it ran fine, once it heated up it would spit, sputter and quit. The problem was intermittent and totally unpredictable as to when it would do it next. I finally tracked down the problem, and subsequently learned (even though the service manual made no mention of this) that the computer will shut down the engine if it detects a low/no oil pressure reading from the sensor, which is what was happening, since the computer would get a zero reading when the wire separated. It may be wroth looking into, you may have a similar issue. Rare, but did happen!

Battery is hooch, Or not a big enough battery,Not enough amps, For all the equipment in the car,

Tank needs to be cleaned out and install a new fuel pump.

Sounds like a weal fuel pump.Check your fuel pressure it should be 48-55 psi with key on and engine off.If its not not within these specs replace fuel pump.

electrical is the weakest link-you may have a computer with issues and before replacin a reprogram should be considered--what did vehicle scan tell you? Data recorders are often placed in cars that show no codes--Older cars can have solenoids and components that heat up and stop engine--if theres a distributer cap-inspec for corrosion

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Is the Service Engine Soon (or Check Engine) light illuminated on the instrument panel? If so, then have someone pull the codes and post them back here. Autozone will do this for you at no cost.Caution: don't purchase any parts after reading the codes on their recommendation! If no codes, then suspect either a bad crankshaft sensor or camshaft sensor. There are other possibilities too, but these are primary. I have seen MANY bad crank sensors do exactly what your describe without setting a code.

try replacing some fuses..... email me a pic of the fuse panels [email protected]

when you say stalls, do you mean shut off of just get low on power?

my check engine light comes on and then oil press light come on and the car shuts off but the lights and music stayed on.
if its that the car needs oil and shuts down to protect itself but it will turn on minutes later.

if stalls periodically, shows check engine light and the car looses a bit of power, in the engine, :

1. your coolant may be having problems getting to the engine in the way it was met to get to the engine

2. the belt might be a bit off and that could be why you get the slipping feeling

3. your exhaust may be a bit clogged. or your engine may need cleaning

i had both problems my car shut off and my engine was slipping. my EXPENSIVE but great machanic found out it was my oil level and my coolant was rusty and not getting to the engine. now she drives like the original 97 olds 88