mb1000

Car stalled while driving on the local road. Turned out to be a 30A fuel pump fuse blew (Fuse #118), benind the rear seat armrest.

Replaced fuse and car started up. After few miles driving fuse blew again. Now I'm thinkng there is something wrong and car is not safe to drive.

Could be fuel, pump, wire or relay caused this? If you had same issue before, please share the fix.

Also, does anyone have pump replacement procedure / diagram? Car has 39k mile on the clock and out of warranty.

Thanks

listerone

IMO that's a safety issue that should be addressed immediately by someone who knows what they're doing.Unless you're a true expert this isn't a DIY job.

mb1000

You are right, it is a safety issue. It's like a car ran out of gas when fuse blew and I had to apply brake harder to stop the car. I'm not going to drive the car till it is fixed

After replaced another 30A fuse, the car runs fine from test drives. There is no code or message there. The problem now is how to reproduce the issue. I tested that the current is around 9-10A at 2-4000 RPM now. I can use my engineering background with some help or bring car to dealer if issue reproduceable.

mb1000

Update

Looks like this is not a common problem as there is no response with same issue.

I got feeling that bad gas can be the cause (water, particles, etc).

I ran car at idle and burned all gas. Bought a pack of 30A fuses, filled up with different brand gas, drove 200+ miles without an issue. It is still hard to tell though. If fuse blew, I can prove the problem still there but not the other way around.

Searched internet and there were some reported issues. After replaced fuse, their car run for 2+ years and do not have problem. Anway, move on and prepare for stop.

listerone

You don't say if the steps...and conclusions...you've specified were done/reached by an expert (dealer,Indy shop) or by you.I hope it was the former.However I,a non-expert to be sure,am having trouble imagining "bad fuel" causing a fuse to blow....more than once.

Well,hope things are now back to normal.

mb1000

After I opened the cover of the fuel tank where fuel pump is in, I found there are wires to the fuel pump and the red one got cut! I can see the burning marker on the wire.

That's it. There is a very sharp edge on the top portion in the fuel tank where wires go through. If I keep driving the car, sooner or later the fuse will blow again and can catch fire.

I made a quick fix by routing wires through a gas resistant plastic pipe and rerouted wires a little bit. Feel much safe now.

I think this is definitely a design or manufacturing issue and should warrant a recall. Don't know how many W221 out there like this.

I took good pics and will send to MB and report to NHTSA.

listerone

This,IMO,is clearly a serious safety issue and if yours wasn't a "freak" occurance then a mandatory recall certainly could be called for.