Will not start

You could try the old fashioned way of checking your mileage. Start with a full tank of fuel. Make a note of the total mileage on the vehicle. Drive the vehicle normally normally until the low fuel light comes on. Refill the tank to full and write down how many litres/gallons you put in. Next check your total mileage display again and write that down as well. From those numbers you can work out you fuel consumption.
Subtract you first mileage number from the current mileage number to get your total miles driven. Then it's Miles driven divided by gallons of fuel used.
As most European pumps measure in litres you'll need to divide the total litres you used by the number of litres to the gallon. Then you can divide the mileage done by that number.
*Note* The American gallon is smaller than the UK 'Imperial' gallon so make sure you use the correct one.
[ UK = 4.55 litres to the gallon (Imperial)].
[ USA = 3.78 litres to the gallon].

Raising the idle would only put undue wear on the transmission shortening it's life. If pressure is low, you may need to replace a worn oil pump. Or depending on the mileage and maintenance, you may need to rebuild the engine. I am driving a 97 5.2l with full tow package with 216,000 miles on it, and I service it faithfully. It still does't smoke or use oil. The pressure does drop to about 20 when idling ( On the dash gauge, who knows how accurate it is ) then goes up to 40 when accelerated to start out. Sounds to me that your problem may be oil pump. FYI if you have very bad gas mileage, I have found a trick that will increase it. replace the stock fuel injectors with 5 hole pontiff injectors from early 90's neons. They are a perfect fit & increased my mileage 25% +. Good luck

By doing this is illegal, there is really no reason to do this !
only if you are trying to cheat your lease, or the next person buying your car,
I could tell you, its easy to do, ok here is how you do it !
To do this to keep the mileage low or not adding up.
What you do is, put your key in the ignition, turn it to the on position ten times, in a row not starting your car, then within 30 seconds get on of your car and place key in your door lock, turning it to the lock position, then take your key FOB and press the lock button 3 times with the key still in the lock cylinder turned to the lick position.
Wait 5 minutes, then disconnect your battery and wait 5 minutes, then hook your battery up again. If you did this right, you have now just overider your computer, to disconnect your mileage, if not repeat.
Now to have your mileage start to record again, place key in your ignition, turn to the on position, not starting your car, do this 5 times, after this is done, on the last turn leave it in the off position, press and release your unlock button on your key FOB 3 times, then disconnect your battery for 5 minutes and connect it back, now your mileage with record now.
Remember I told you this is illegal to do, there is really no reason to do this

The computer for your car has a specific program for that car. You need to have the second computer flashed with your program, mileage and VIN number. It is extremely rare that a computer from another car, even the exact car, will work without the program being flashed.

check if have the same numbers en the tag because sometimes it's different code if is the same the computer is not good

tune up. Good starting point.

mass air flow sensor, O2 sensor..... could be many things.

first get sec. opinion. Could just be out of time through your distrubuter or bad cap .good luck .

Look for good ground connections. Your description sounds like low battery state of charge, then voltage goes too low on start up...Check charging system and load test the battery. Check ALL connections.

If this is a high mileage vehicle, say 180k or higher, treatments are not going to help. As mileage increases, the tolerances and clearances in the mating parts increases. This will lower oil pressure. I have a 90 Safari with 192K. Oil pressure was identicle to yours. I put new rod and main bearings in it and now it never goes below 40 psi, even when hot and idling. I tried additives and all I got was more trouble, It started smoking and using a qt. of oil every 300 MILES. I put valve stems seals in and it helped alittle but not near enough. It is now parked and driven only when have to. This is a result of the previous owner of my vehicle not changing oil at regular intervals and overall poor upkeep of it.

Good Luck

Nowdays 1 Qt. in 3000 miles, really isn't that bad, even some new vehicles claim that's normal. I know with my current vehicles, both at approx. 150,000-160,000 miles, they won't use any for first while after an oil change, but then after mileage starts adding up again, they start to use a little, approx.I Qt, every 1000 miles or so, until it's changed again. I've switched to the high mileage oil, just for piece of mind, as they say it revives seals, and has added protection for the higher mileage engines.This time around I'm thinking of adding "Lucas" & see how it works, as I've heard some pretty good reports on it, just to see if it will prolong that oil breakdown, at mid change.