97 Nissan Sentra will start but won't stay started without foot on the pedal what could be the problem

Start with lubricating the clutch pedal pivot up under the dash. Then check the hydraulic components in the system. There is a flexible rubber hose that connects the clutch slave cylinder mounted on the transmission case to the metal tubing from the clutch master cylinder. The inside of the hose can deteriorate internally without leaking to the point where it will pinch off or restrict the fluid flow which causes a stiff pedal.

check your fuses under the hood

replace ur crank/cam sensors. without a proper signal form those ur car will turn over forever without starting.

Sounds like a fuel supply problem. The fact that it does momentarily start, indicates its not an electrical issue. However, no steady fuel supply to the injectors and it won't run for more than a second or tow. Your problem is in the fuel delivery system most likely. Either the pump, or (if the unit is located in the fuel tank) the fuel filter may have ruptured. That would sent all the fuel back to the fuel tank not to the injectors.

ok i have a 1998 durango with the 5.2L 318 engine. had trouble with a bad cell in my battery. I went out bought an optima red top battery for it 800cca. put it in and had same trouble. No start without putting foot on gas. wouldn't stay running without holding foot on gas. CPU has to relearn it's programming once you unplug it for long periods of time. mine was without power for about 2-3 weeks till i got new battery. Start with this.. first check under air filter make sure a squirrel hasn't made a mess under your air filter and it's clogging the air intake. Then pull off the lid to your injector cover ( the screw down lid coming from the air box ( with air filter in it) to "carb") make sure all your cables move freely. put that all back together and close hood. Start truck with foot slightly on gas pedal to get started. keep it at about 1k to 1500 rpm for about 1-2 minutes. Rev motor to about 2500rpm and let it die out if it will. Get out lock doors with key fob if you have it. if not make sure to lock doors. ( trust me it worked for me) let sit for 5 minutes. come back out and unlock door and relock door 3 times with fob ( if you have it ) or key if you don't have a fob. Then unlock it with the key and enter vehicle. Start truck as before and keep it around 1k to 1500 rpm again for about 30 seconds rev it up and should keep running. Mine did. I think the iac was stuck from sitting and has now since loosened up.
Good luck hope ti works for you.

It could be a number of things. Have you tried to run any codes yet?

Yes, there is a switch on the pedal, just like on the brake pedal of automatics. There are 2 locks, yours is electric, but the key lock is manual, it has to be on. Which it would be if you were trying to start it, but on the automatic, it goes from the key to the shifter with a mechanical lock, also the brake pedal is wired into a solenoid on the shifter, won't move without your foot on the pedal. Sometimes it has to be in neutral to start. Check it out.

Hi it sounds like you have noisy tappits you could try using a thicker oil speak to a local car spares shop about this as this might solve your problem if not then it would be a case of replacing the hydraulic lifters this is quite a big job and something a novice should not attempt but if the noise isnt to bad then its not going to wreck your car if after time the noise gets louder then you would need to get these parts replaced.

let me know how you get on or if you need further assistance ok

Could be TPS, could be clogged cat converter, could be fouled/worn spark plugs, could be not enough fuel pressure, could be timing, could be......

is it a manual or automatic?if it's manual check clutch.if it is automatic check transmission fluid.