No start: fuel issue

[HennaE30]

So I'm stumped. About a week and a half ago I was pulling out of walmart, when all of a sudden I lose power, and the rpm just steadily dropped (like it was losing fuel pressure).

I assumed it was the fuel pump, because I was having issues the week before with fuel delivery, the car wouldn't want to idle and you could hear the pump hum.. The humming promptly stopped.. And I forgot about it.

So after a week and a half of waiting for the fuel pump from IE, I put it in yesterday, crank it, no bueno.

So I checked the pump relay, getting 12v there. None of the fuses are blown. But I'm not getting power at the pump.

Where do I go from here? Thanks ahead of time guys. Helping out an E30 noob is good karma :-)

[vpilarrt]

Check fuse 11? It's after the relay.
Check out page 110 in the 325e section: http://wedophones.com/Manuals/BMW/19...g%20Manual.pdf

[HennaE30]

Check fuse 11? It's after the relay.

I've checked all the fuses. 9, 10, 11, and 21 (I believe are the relevant ones)

[spdracrm3]

year and model?

if engine stalls fuel pump will stop running (so humming will stop)

ECU has to see a cranking and rpm signal to turn on fuel pump relay (there is no priming pulse when key is turned on initially also) .what pin are you seeing power on ?

you can jumper the fuel pump relay and see if pump runs pin 30 to 87 on relay socket(also try to start with pump running ) if it wont run check for spark . its possible your crank sensor isnt working causing no fuel pump or coil control

[HennaE30]

year and model?

if engine stalls fuel pump will stop running (so humming will stop)

ECU has to see a cranking and rpm signal to turn on fuel pump relay (there is no priming pulse when key is turned on initially also) .what pin are you seeing power on ?

you can jumper the fuel pump relay and see if pump runs pin 30 to 87 on relay socket(also try to start with pump running ) if it wont run check for spark . its possible your crank sensor isnt working causing no fuel pump or coil control

84 325e

I meant that the idle/run smoothed out and the fuel pump stopped humming for a couple weeks, not that it shut off after it stalled. Sorry if i wasn't clear

I had read that the ECU had to see cranking, which is making me think it may be the crank position sensor? With the car on run, im getting power at 30, 85, and 86, with the 87 being the ground, is this correct?

I read a bavauto article that says you should get 12v at pin 30 regardless of key position, i can confirm i am getting power at 30.

Sorry I cant be clearer, im trying to be as helpful as i can

[HennaE30]

No start: fuel issue

So looking at the PDF (thanks vpilarrt for the link) I'm going to check the CPS tomorrow to see if it's faulty, because I'm getting power though the relay, and the fuse isn't bad (I ran a continuity through it). I don't think the CPS is sending the signal that the crank is turning to the relay, which isn't passing it down the line to the fuel pump.

Any tips on checking to see if the CPS is bad?

Thanks for your help. I'll check that tomorrow and get back to you to see if that fixes it.

[HennaE30]

Replaced the CPS. Still nothing. I'm out of ideas... Anyone else know what it could be?

[spdracrm3]

84 325e

I meant that the idle/run smoothed out and the fuel pump stopped humming for a couple weeks, not that it shut off after it stalled. Sorry if i wasn't clear

I had read that the ECU had to see cranking, which is making me think it may be the crank position sensor? With the car on run, im getting power at 30, 85, and 86, with the 87 being the ground, is this correct? which relay? ,pin 30 is battery voltage ,pins 85 and 86 are the relay control side one pin will have battery voltage one will have a ground controlled somehow to turn relay on , 87 is the power out to whatever device is being controlled by that relay (it will often have a ground signal if tested with relay off ,this will be the ground coming thru whatever is on the circuit back to the relay)

I read a bavauto article that says you should get 12v at pin 30 regardless of key position, i can confirm i am getting power at 30.correct ,pin 30 is battery voltage that is switched buy the relay for fuel pump and injectors

Sorry I cant be clearer, im trying to be as helpful as i can

So looking at the PDF (thanks vpilarrt for the link) I'm going to check the CPS tomorrow to see if it's faulty, because I'm getting power though the relay, and the fuse isn't bad (I ran a continuity through it). I don't think the CPS is sending the signal that the crank is turning to the relay, which isn't passing it down the line to the fuel pump.

Any tips on checking to see if the CPS is bad? ohm test the sensor then check at correct ECU pins for crank sensor for AC voltage signal while cranking with DVOM. if no siganl present may be a wiring issue .if signal is good might be an ECU problem.

Thanks for your help. I'll check that tomorrow and get back to you to see if that fixes it.

[HennaE30]

No start: fuel issue


What do u mean wiring issue?

We are not getting spark or fuel, but all the components are getting power, except the pump.

[spdracrm3]

What do u mean wiring issue?broken wire ,melted wire ,bad/corroded connector . testing at ECU will confirm signal is making it to the ECU

We are not getting spark or fuel, but all the components are getting power, except the pump.you wont without a good crank signal at ECU to control coil and turn on fuel pump relay or fire injectors .

looking at an ETM looks like you can test the crank sensor (ETM calls it a TDC sensor)at the diagnostic connector at pin 8 and 10

also do you have a 13 botton OBC?

do you have your ETM downloaded ? http://www.wedophones.com/BMWManualsLead.htm

[HennaE30]

Yes I do.

[416stroker]

If you have the 13 bottom OBC could be the relay off that. Does it have 12v to the coil if not it runs thee that fist had that problem once I forget what it's called I traced it out till I found it


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[416stroker]

No start: fuel issue

Also it's under the dash looks like 1.5"-2 rectangular box I think? It's been a few years
Though

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[HennaE30]

Yea, I know what your referring to. that's how I fixed my AC. So your saying check for power in the pins of the connectors?

[HennaE30]

No start: fuel issue

Also it's under the dash looks like 1.5"-2 rectangular box I think? It's been a few years
Though

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So I checked the voltage on the 2 plugs that plug into the box.. The plug with 2 pin holes on the the outside, I got 12v but the other (with 3 pin holes) I don't get any power. Is this part of the issue? I don't really know what purpose the box serves

Also not sure if this helps at all. But there's 4 beeps after I turn the car off. Not sure if that's factory or an aftermarket alarm.
I also have a weird orange light that lights up under the steering wheel whenever the key is in the run position