Hi: guys, I am new in this forum and I will thanks' in advance for the advice you going to give me on this issue.


I have a Mercedes s420 1999, I didn’t use the car just for short drives and twice in month start it up just to warm it. Last day when it’s running to warm it’s up, stop working and just shoot down I presume its empty of gas because that fuel light still on, I start over and aver tried get it running but won’t crank. Until tent to twelve minutes I tried again, its run but shoot off quick. I still thinking that need some gas. in the mean time I am waiting for a key fob from EBay because mine become broken’ when tried to start over and over the car, and as soon as got it I do the change between fobs and apparently its work fine all the operations regards to the key working good likes, lock and unlocked the doors the trunk and the windows. Next week after that I put some gas “5 Gallons” and then I tried again to start the car start but don’t want to running, don’t crank up.
I check in the odometer display and see a code “ start error” I will check if the fuel pump have been working but any kind of noise coming from the pump, I thought, maybe the filter become clog when the tank was empty. Took out the pump and filter not too much dirt in the filter and the pump work good, put then back, I noticed in the port where the pressure gage will be connected to check the fuel pressure, the pressure don’t locks like has from 45 to 50 PSI, well I don’t have the gage to confirm this but I know what’s 1 PSI means in pneumatic flows regards. well I precced to check almost many thinks o the car, Just to lets you know I check all this, as follow”
1- Fuel pump and filter, working good apparently.
2- The voltage in the injectors was 6.5 volts with the switch in third position, 5.5 when start I didn't know if this is the normal voltage requirement on the injectors power.
3- 11.5 volts in the fuel pimp connector when start.
4- Ten volts on the can sensor plug.
5- No resistance on the can sensor.
6- The Map sensor burn in up, I didn’t know if this is a fault to display the error start code.
7- Map sensor hose was broke I replaced it for a new one any way.

Well I decided to put some mist of gas truth the flow Metter and the car motor rand for a while until consumed the gas. I didn’t know if this test means something to you, but means that in the coils we have power.
Other possible problem is the key maybe have no signal to the ring and the chip gone. But you are the expert, so any advice from you is welcome
Thanks in advance.
I am from Puerto Rico, so my English is no so well, did my best on this.