Mercedes-Benz Forum banner

1 - 2 of 2 Posts

·
Registered
Joined
·
2 Posts
Discussion Starter #1
Hey guys, new to the forum. I just picked up a 1990 420SEL from a local military general, he was the original owner. He told me the fuel pump was bad. nothing major so i got a good deal from him and towed it home. Changed both pumps from another running 420 we had around and also did a tune up with fuel filter, plugs, wires, oil change. Well the car started up and you could drive it for about 10 minutes then it would die, would usually start right back up but sometimes you would have to wait about 5-10 minutes. sometimes you could drive it for 30 miles if you didnt go past 1/4 throttle. Weird. but today i went to start it and i didnt hear the fuel pumps turn on at all, cranked it and nothing. checked the FPR and removed it and jumped it, still nothing, checked with test light to see if there was power there and there was. went to see if the fuel pumps were getting power and they were not. i can take a jumper wire from the battery and touch one of the fuel pumps and it will start. im lost now on this, is their anything that could stop power from getting to the fuel pump between the relay and pump.
 

·
Registered
Joined
·
2 Posts
Discussion Starter #2
ok did some more work on it today, i just wired the pumps dirrectly from the battery to get them workin, they seem to be very noisey. i can start it and it runs fine in park, when in gear its also fine, i can drive it around with slight throttle but if i press it more than 1/4-1/2 throttle it will just die. after about 1-2 minutes of sitting their it will start again, im thinking either one of the fuel pumps is bad or fuel filter or accummulator. any ideas guys?
 
1 - 2 of 2 Posts
Top