Firstly, the car is a 1985 325e. Other possibly relevant information is that I recently raced a rallycross with it which was extremely muddy. Like, a foot deep kind of mud where people were consistently getting stuck. Everything went well and it ran like a champ.
Then the other day I was driving it to the gym and all of a sudden it sputters out and dies, acting like its running out of gas, which seemed possible given my non-functional fuel gauge. I poured some fuel in but it just cranked over until the battery died. Awesome. So I towed it the few blocks home with my STI with a 6,000 lb strap which promptly broke and I had to rig back together.
Anyway, I start looking into the fuel pump and poking around. All connections look good. I decide to randomly try to start it with a charged battery. Boom, starts right up. I thought this was odd but thought maybe it had run out of gas and it took a bit to get fuel through the lines, however unlikely.
This brings us to Sunday, when I took it 75 miles out of town to go for a hike. Brilliant, I know. It ends up doing the same sputtering and dying thing, but I know it has fuel. I brought a handful of tools, test light, and multimeter in anticipation of this. I quickly realize that I'm getting no power to the fuel pump. So I look at the fuses and they're all fine. I then look to the relay and I'm not getting power to any of the pins of the fuel pump relay. So jumping pins won't start the fuel pump. I jumped two pins on the DME relay and the fuel pump relay at the same time and the fuel pump ran but it still wouldnt start.
At this point I decided I must not have spark so I checked the coil, and sure enough, no power to the coil. Fantastic. At this point I'm running out of battery from trying to start off and on and I didn't know you have to bridge three pins on the DME relay so I have it towed (Thanks AAA).
Immediately I swapped in a DME relay I had from a parts car and I am now getting power to the coil, but still not to the fuel pump or fuel pump relay. I gave up for the night.
Yesterday, I thought I'd crawl under to see if the wires to the CPS sensor(s) were severed by a rock or something. All the wires looked fine but the sensors were coated with mud. I picked off a bit of the caked on mud and decided to work on it later but before I went inside I cranked it over and it started immediately like nothing ever happened.
So really, would a moderate amount of mud interfere with the CPS sensors? I can't make out how that would work. Could it be that the old relay as well as the spare one I swapped in are both working off and on?
I don't think it's a problem with any pumps themselves because the problem was getting power to them. Any insight?
Thanks for any help and sorry for the length of my post.
Then the other day I was driving it to the gym and all of a sudden it sputters out and dies, acting like its running out of gas, which seemed possible given my non-functional fuel gauge. I poured some fuel in but it just cranked over until the battery died. Awesome. So I towed it the few blocks home with my STI with a 6,000 lb strap which promptly broke and I had to rig back together.
Anyway, I start looking into the fuel pump and poking around. All connections look good. I decide to randomly try to start it with a charged battery. Boom, starts right up. I thought this was odd but thought maybe it had run out of gas and it took a bit to get fuel through the lines, however unlikely.
This brings us to Sunday, when I took it 75 miles out of town to go for a hike. Brilliant, I know. It ends up doing the same sputtering and dying thing, but I know it has fuel. I brought a handful of tools, test light, and multimeter in anticipation of this. I quickly realize that I'm getting no power to the fuel pump. So I look at the fuses and they're all fine. I then look to the relay and I'm not getting power to any of the pins of the fuel pump relay. So jumping pins won't start the fuel pump. I jumped two pins on the DME relay and the fuel pump relay at the same time and the fuel pump ran but it still wouldnt start.
At this point I decided I must not have spark so I checked the coil, and sure enough, no power to the coil. Fantastic. At this point I'm running out of battery from trying to start off and on and I didn't know you have to bridge three pins on the DME relay so I have it towed (Thanks AAA).
Immediately I swapped in a DME relay I had from a parts car and I am now getting power to the coil, but still not to the fuel pump or fuel pump relay. I gave up for the night.
Yesterday, I thought I'd crawl under to see if the wires to the CPS sensor(s) were severed by a rock or something. All the wires looked fine but the sensors were coated with mud. I picked off a bit of the caked on mud and decided to work on it later but before I went inside I cranked it over and it started immediately like nothing ever happened.
So really, would a moderate amount of mud interfere with the CPS sensors? I can't make out how that would work. Could it be that the old relay as well as the spare one I swapped in are both working off and on?
I don't think it's a problem with any pumps themselves because the problem was getting power to them. Any insight?Thanks for any help and sorry for the length of my post.
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