Hit BIG bump car "ran out of gas"
 

Stumped... 1992 300 wagon 2wd

5/8 fuel load, hit a LARGE frost heave, and car acted like it ran out of gas... It didnt spit or sputter, just bwaaaa to a stop.. Can hear the fuel pump pump and stop, car will attempt to start (like its running on fumes only)

Ether and it starts and runs fine.. but no fuel is getting in the motor..

next going to check at rails for fuel.. Any other ideas or suggestions are much appreciated, it's my only trans at the moment and well it goes over frost heaves USUALLY much better than I do walking!

Thanks in advance Karl

I know Fords have an intertia switch that's meant to cut off fuel supply in a crash. Sometimes they get tripped other ways. Anyone know if Mercedes ever used a similar idea?

Fuel pump relay cuts off fuel supply when the engine is not running.
Not sure however if your 104(?) combined the FPR with another module in the later years.

Yes it is 124 sorry...

Fuel pump relay? Is that like a gate valve? Or does it simply send power to pumps? Sorry if I sound Naive .. I am..

I hear both fuel pumps come on, and stop.

I really thought this less than 1 minute after it rolled to a stop.. It was a big bump, im sure my rears left the ground... funny how those frost heaves just pop up overnight.. Drive that road everyday...

104 engine?

the relay will be behind the battery with the overvoltage protection relay (red top /w fuse). As I said, I'm not sure if the 104's used the "FPR" or integrated it into a "MAS" type relay.
Either way, find out which you have, get the wiring diagram then remove it and use a wire to jumper it on the correct sockets and see if the car starts.

Well I.. uh... "fixed it" took off first fuel pump at outlet side, compressed air blew in reverse.. turned on key, and fuel sprayed out... hooked it up and wazoo it started as usual... BUT WHAT did I " fix" ? is the big question.... cause it's still in there... Any Ideas?

big bump
 

first thot was inertia sw.,but u said can hear pump prime and stop. should then run during crank. then u said took pump apart and blu thru, dislodged something? hmm debris in tank? check valve at pump output end passes fuel in one direction.sticky? watery fuel froze? (ethanol based fuel turns watery after sitting) we used to sell BG product to emulsify and suspend water so cars could pass their water without pulling tanks. napa can get it. all the methyl ethyl kind are no good 4 injectors. if that dudn work, my pal rubs seafoam on everything as a salve. blo thru the filter, should b no resistance.dumpfilter contents(out the inlet) in a pickle jar, let separate. tells water and debris size and type. happy moteur