RoadkingHI

1997 S420 won't start,
Battery - good
Turn over - good
Spark - good
Weather - good (always:-)
Fuel level - 3/4 full
Last ran - two days ago, ok

Checked all fuses (engine and trunk) - good

Suspect fuel delivery, maybe F/O pump or some type of relay?
Any suggestions as to where to look and/or test?

gogi

check fuel pressure if ok then check for injector pulse. If no fuel pressure check for f/pump relay, probably in fuse box,if ok supply +12v to fuel pump and make sure to give it a good ground to see if it works if ok the problem must be with the injector pulse or no compression. All you need is fuel,compression and spark for a si engine to start.

barry S320V

if you blow the fuse for the cagarette lighter the car will not start. strange but true.

jgen

Sounds like the engine wiring harness to me. I had the same problem with my S500 coupe.

philip29

have you tried to crank it in neutral or run threw the gear while having the ignition in the crank position. because it could be you neutral safety switch. if if does crank in a different gear then it will be your switch. because my had that problem ,all the light lit up at the 2position but would not crank so i just runing threw the gears and come to find out it was my neutral safety switch .causing it not to crank.

RoadkingHI

I posted on the tech part about this but forgot to update all on what I found out.
Turns out the mechanical key portion must be worn as I used the other key that we seldom use and the "engine start" lock out on the computer was cleared and the car started right up.
To test it we use the regular key and didn't work.
Stumped me but appears the key has worn down enough to not allow the engine start to work.
Lot of work for a simple problem... All is well but I have to look for a mechanical key blank for the remote fob.
Thanks for the suggestions and help!