Starts, 35+ PSI fuel pressure, then engine cuts out, will not stay running?

Right off the bat the fuel pressure is low, here are the specs:

Fuel Pressure (Key ON, Engine OFF) .................... 269-338 kPa (39-49 psi)

I would continue with the pump and use an AC Delco unit. Next, I would run the codes and then I would service the throttle bore. Here are two guides to help us fix the problem or at least get closer:

https://www.2carpros.com/articles/checking-a-service-engine-soon-or-check-engine-light-on-or-flashing

and

https://www.2carpros.com/articles/throttle-actuator-service

Please run down these guides and report back.

Gentlemen. Your reply sounds like you really want to help. So, let me begin. This Saturn L300 with 169,000 miles. The past few months. When attempting to start. would not fire right up, instead would slowly run the starter, and after a few seconds maybe up to 10 seconds would start and run normal. Then would start normally for weeks. I had gotten use to this, thinking it had something to do with a bad ignition switch and if it no longer started. I would replace the switch. It has codes. Bad heater on the O2 sensor bank 1. Warm up catalytic thermostat temperature below normal, Coolant thermostat temp below normal, And Transmision control system ML request. The trans ever so often shows the wrench symbol and goes into limp mode but goes away on restart. These Codes pop up, but it ran well otherwise. Result I could clear codes and get it thru inspection then drive around with the check engine light on. This Non running condition is new. The current codes it is throwing out are. PO123, Throttle position senser Hi Voltage. Po222, Throttle position sensor B circuit low, and Still getting Transmision Control System MIL Request. The other codes have vanished because the engine will not start. I watched the Video. on Throttle position sensor cleaning and although I had brushed cleaned it in place, I did not remove it as shown to clean it. This I will do right now and before sending this report on what happens. As to Fuel pump, the highest pressure I am seeing is 40 PSI. My Snap On friend told me last night that this is too low, The Saturn Forum says 40 PSI is good without the engine running. So, I'm still not sure if I have a fuel pump issue. Again, I have the Tank dropped, anticipating a bad fuel pump and will leave it that way until I find the problem. See Throttle activator plug. Two questions. #1 can I put 12 volts to one pin and modulate the Valve to see if the motor works. #2 if I put a 38-dowel in and open the shutter 3/8" would the pump stay running, and the car run at 2000 RPM's? I broke the paper gasket, new one to arrive tomorrow. Shown photos of clean part, and plug.

The throttle position sensor codes are the clue, I would replace the throttle bore or see if there are bad connections at the bore, this should solve your problem here are images below to help. Let me know what happens, we are interested in seeing what it is.

I will replace the Throttle Bore with new as I have no way to test one at a pick and pull. I would guess the next part that can cause this is the Power Control Module.

Okay, let me know.

Ken, I have replaced the Throttle bore. Codes, PO123 and PO222 have cleared. I never got a Fuel pump failure Code. I still see a PO700 Transmision Control System ML Request. I still have 40 PSI fuel pressure before the System appears to cut out. The fuel pump I ordered has shipped and is due to arrive. You said to change it so I will change it, I'm not sure if it is the problem. I have been using an Auto Tap Code reader. It goes from the OBD port to a laptop and with the software and the car running you can see things on the screen in real time. But to see this it has to be running. I had wanted to clear the codes they will not clear.
When I called Auto Tap, to see why I can no longer clear my codes. I found out that the Company no longer supports Auto Tap and they have closed the division that used to offer service. So, do you want to make a comment on a new Code reader? I wish I could afford Snap-On but I'm not a shop and can't see the expense. I also noticed in Auto Taps literature, that they say not to disconnect the battery, as it damages the memory of the PCM. Too late I already did that. Well, Old Saturn still won't start. What would be the next thing to look at in a progress chart?

Will the engine start if you spay starting fluid into the intake? Also, how does the engine sound when you are cranking it over? Please check for spark, this video will show you how:

https://youtu.be/baq_aEWNQ0Y

I would get this scanner because it does more than a snap on and is only about $279.00 instead of 8g's like the Snap-On unit.

https://amzn.to/3AKfsJe

Let me know what you find.

I just bought the NT716. What advantage would it be to also own the GT60 I see it can be bought at a later date. Do any of them allow you to toggle on the fuel pump? Like a Snap on Tool. Advance the Throttle. Start and stop the car remotely. The NT 716 has a lot of diagnostic functions that lead you to check issues until you find a problem, which looks good. GT60 looks like it would work on an older OBD 2 car. Did not find if it does Saturn, Pontiac, or Oldsmobile now that they are no longer produced. The free updated software is definitely a plus. I think I am losing spark. I will test this. I will also spray some starting fluid into the intake somehow, that along with the spark should tell me something. I am still waiting for the new Fuel pump.

As far as the functionality is concerned you will need to read the manufacturers' list of scanner capabilities. Let me know what happens after the fuel pump.

Okay. Thanks' still waiting for the fuel pump from parts Geek.

Okay. Best news. New Fuel pump and Throttle Body are installed. Also bought the Foxwell Scanner NT7X6 you recommended. Very anxious to try scanner, unfortunately the battery was too low to get accurate scan. But what I got with battery at 7.8 volts was P2176 minimum Throttle position not learned and P102 MAF voltage Low. Will try again with full charged battery. After new fuel pump: although fuel pressure gauge still went no higher than 40+ Car would start and run at 3,000-4,000 RPMs but would stall at lower than 2,500 RPMs. I take this as some progress. New scan tool I'd the PCM as #12584403XF and Trans TCM as #245228727AA I am sending what the scanner saw. But must send with Outlook Mail.

New scanner Foxwell NT7X6, I can't figure out how to send report. But it says P2176 Minimum throttle position not learned & P0102 Mass air flow (MAF) circuit low Voltage.
This may be a result of a Low Battery. Charging battery in progress.

List of faults: P2176, P0102, P0526, P0705, P0712, P0716, P0717, P1780, P1810, P1831, P1833, P1842, P1843. Also, P1025 and P1021 Saying to refer to the Saturn Service Manual.
I'm learning that I need to tow it to a Chevy Dealership, and have them reprogram something? What do you think?

Some new information, about L3oo Saturn that will not stay running. First because I was getting so many low voltage codes, I replaced the Battery. Then scanned it again Getting one Code: P0102 MAP air senser low Voltage. Testing for the MAP say's car should be running, well that's not happening. Also, when new battery installed, I noticed a yellow dash light flashing on-off, on-off this light looks like a padlock with an (i) in the center, that is overlaid over a Car to its left (you can see like the windshield the front of the car body and one tire the rest of the car is hidden by the padlock. This image is not shown in the Saturn owner's manual as a trouble light. It is at the bottom center of the instrument cluster.

Just found out this Dash light is a security indicator. I doubt if it is telling us anything.

It sounds like the BCM or PCM is out, can you do a CAN scan to see what comes up? You can get a CAN scanner (Controller Area Network) from Amazon for about $30.00.

Here is a video to show you how:

https://youtu.be/u-4syLc-ifQ

Ken, this sounds like a device that is a must have for the newer more complicated cars. Ryan, from 2CarPros says The All-Data reader is the one to have. My question is, when ordering the Foxwell NT7X6 There was an additional tool, a Code Scanner that could be had for an additional amount of money. The Foxwell tool was more money than what Ken says the All-Data too costs. Would the Foxwell tool be the better buy? even if it costs more money. Currently, I went to Chevrolet Service manager he says they can reboot the PCM/ECM software for $165.00 If that's all there is, then its fixed. After replacing the battery. The new code its throwing is P0102 saying Low Voltage at the MAP sensor. I'm beginning to believe that it is the PCM. that I am calling the ECM. Although, I would like to purchase more of the proper test equipment to be able to diagnose More Vehicles. At this point I just want this car back on the road. You have been more than helpful, what is your opinion about buying the Foxwell tool or the All-Data tool? What I am hearing is even if I were to have a CAN reader and it said the PCM was out of calibration, I would still have to go to a Chevy dealer to have it reprogramed? Not saying I would not buy the tool, just thinking the Chevrolet dealer is my only real option here.

Just looking up some info on Foxwell GT601 Foxwell does not say it is a CAN BUS scanner.

You need to have a CAN scanner; did you check the link above? It is only $30.00 but they have better units. Also, you can get a rebuilt PCM per-programmed if you search google or eBay. Here is the location of the PCM and how to replace it in case you need it.

I am ordering the CAN sensor tool from All-Data recommended by Ryan. I am still towing the car to Chevy. Buying a used PCM on eBay sounds risky. If Chevrolet finds the PCM is shot. I will do this. I went over all the car's faults and history with the Service manager at Chevrolet, and he is going to try to reflash the PCM. As you both agree this may be the issue. If not, I will tow it back to my shop and read the CAN with my new All-Data senser. Either way I will get back to you. I watched Ryan's YouTube Wednesday night live and saw a reference to www.instigram.com/ryans garage. but it would not load? On the air, real time help like this is a great help when you're stuck with a problem. Again, I will let you know what develops after a re-programing and diagnostic by Chevrolet on Thursday. I will look into buying a re-programed PCM on eBay, but I saw used Throttle bodies on eBay yet bought a new one. Because I did not want to take the risk. Bill

I looked at the All-Data. DYS, agreement as you said there is a cost involved to use this software. I cannot find the price of the Tool/reader itself. I don't know if I am ready for this All-Data subscription. Ancel AD310 reader is on Amazon for $26.00. It says it's a CAN and diagnostic tool. As we all know you get what you pay for. I am at a loss as to what to do. I think I will stay with the plan and let Chevrolet reflash the PCM and start from there. Again, I will let you know what happens.

Sounds good, let me know. BTW this is the scanner we are recommending now:

https://amzn.to/3eCqWWw

Sorry for the confusion.

Thank you for clearing this up. I know that I need something more than the NT7X6 Foxwell. But I'm not ready for The All-Data subscription service as a DYS guy. I ordered what you recommended. If Chevy does not fix the problem and does not give me new codes to look into. It will be good to have this tool. As far as flashing a PCM I guess only Chevy, in this case or another manufacture has the software to do this operation. I know VW is very secretive. Dealers have to contact Germany to program an ignition key.

Yep, you can get a preprogrammed PCM from services online though. Just give them your VIN and they send it ready to go. Search Google and Ebay

I do not know if you received this. The car came back from Chevrolet running/but with the MAF disconnected. As a novice, I can't see how the car can run without the MAF. Doesn't the MAF tell the PCM the amount of air so that the throttle body can adjust the gas to air ratio accordingly? I will replace the MAF and plug it back in to see if the car still runs. My situation is. Do I buy a middle of the road brand new MAF off Amazon? that is recommended for a Saturn L 300 3.0 for $64-$89.00, or should I get an original Bosh, PBT-GF30 from a salvage yard or Ebay seller for $50.00 if I can find one, chevy price for this part is $293.00 Genuine Bosh for this car of the internet is $149.00. Again, I am awaiting your reply. how best to precede. Glad the car is running, but I'm stumped as to what to do next.

So, without the sensor plugged in the PCM substitutes a default valve for the sensor input, but if the sensor is plugged in and is telling the PCM there is no air entering the engine the PCM will shut down fuel. I would get the Bosch unit. Let me know how it goes.