84 318i owners, help me troubleshoot this

[James Crivellone]

Hey guys,


a few weeks ago a friend of mine picked up a beat up 318, unknown milage, (over 220K easy) and it had been sitting for 3 years, now the good part is that he only paid 100 bucks, so its a good project/first car for him (imho at least)


I spent today trying to get it running again, replaced the battery, and did a general inspection, we also drained all the old fuel and replaced it with fresh 87 octane. oil levels are good, as well as coolant. Once I get the car actually running all fluids will be changed of course.


My issue is actually getting the car to start, the engine will start, rev to about 1500RPM and then just die, so it runs for around 2 seconds.

I have checked the entire electrical system, all DME Pins, injectors, airflow, ignition switch tests good as well.

The car ran when it was parked, so I am thinking its a relay or something under the hood that has died. The fuel pump does shut off after I stop cranking the engine, so I am guessing a bad relay perhaps?

Another thing, there is a 3 pin connector near the AFM, that is just sitting there, doing nothing, It looks similar to the altitude sensor on my ETA, however I can find no reference to this.

So where should I go from here? I am trying to track down some engine relays locally, as I don't have any for a 318i, but I thought I would get some other opinions. Also could it be the ECU?

[Rigmaster]

Re: 84 318i owners, help me troubleshoot this

Hey guys,


a few weeks ago a friend of mine picked up a beat up 318, unknown milage, (over 220K easy) and it had been sitting for 3 years, now the good part is that he only paid 100 bucks, so its a good project/first car for him (imho at least)


I spent today trying to get it running again, replaced the battery, and did a general inspection, we also drained all the old fuel and replaced it with fresh 87 octane. oil levels are good, as well as coolant. Once I get the car actually running all fluids will be changed of course.


My issue is actually getting the car to start, the engine will start, rev to about 1500RPM and then just die, so it runs for around 2 seconds.

I have checked the entire electrical system, all DME Pins, injectors, airflow, ignition switch tests good as well.

The car ran when it was parked, so I am thinking its a relay or something under the hood that has died. The fuel pump does shut off after I stop cranking the engine, so I am guessing a bad relay perhaps?

Another thing, there is a 3 pin connector near the AFM, that is just sitting there, doing nothing, It looks similar to the altitude sensor on my ETA, however I can find no reference to this.

So where should I go from here? I am trying to track down some engine relays locally, as I don't have any for a 318i, but I thought I would get some other opinions. Also could it be the ECU?

Jumper the fuel pump relay (so it runs all the time) and see if that makes a difference. Sounds like you are on the right path- don't start blaming bizzare stuff like ECU, etc- generally when they go bad- the car won't run at all.

Bret.

[James Crivellone]

Re: 84 318i owners, help me troubleshoot this

Hey guys,


a few weeks ago a friend of mine picked up a beat up 318, unknown milage, (over 220K easy) and it had been sitting for 3 years, now the good part is that he only paid 100 bucks, so its a good project/first car for him (imho at least)


I spent today trying to get it running again, replaced the battery, and did a general inspection, we also drained all the old fuel and replaced it with fresh 87 octane. oil levels are good, as well as coolant. Once I get the car actually running all fluids will be changed of course.


My issue is actually getting the car to start, the engine will start, rev to about 1500RPM and then just die, so it runs for around 2 seconds.

I have checked the entire electrical system, all DME Pins, injectors, airflow, ignition switch tests good as well.

The car ran when it was parked, so I am thinking its a relay or something under the hood that has died. The fuel pump does shut off after I stop cranking the engine, so I am guessing a bad relay perhaps?

Another thing, there is a 3 pin connector near the AFM, that is just sitting there, doing nothing, It looks similar to the altitude sensor on my ETA, however I can find no reference to this.

So where should I go from here? I am trying to track down some engine relays locally, as I don't have any for a 318i, but I thought I would get some other opinions. Also could it be the ECU?

Jumper the fuel pump relay (so it runs all the time) and see if that makes a difference. Sounds like you are on the right path- don't start blaming bizzare stuff like ECU, etc- generally when they go bad- the car won't run at all.

Bret.

I jumped the fuel pump, still did not start,


the car will run for 2 seconds even with the ECU unplugged, sounds like its getting fuel only from the cold start injector

[grlaneriejr]

Does it have the right fuel pressure? Sounds to me like the cold start valve is the only thing getting gas to it. Check the fuel filter and all that.

If not that, try this. There are 3 relays on the driver's side fenderwell. Make sure there is not a "ticking" niose coming from the relays. One of them is called the "fuel pump crossover relay". I had a problem on that with my 85, and when I slapped the relay, it would run okay for a while.

Hope this helps.

[James Crivellone]

I even tried bypassing those, still would not fire.


I cracked the fuel line on the fuel rail, and I had plenty of fuel, good pressure from what I can tell.

I may have to pull the fuel rail and inspect it

[318driver]

On my 318i the idle control valve never ran right so when i would start the car, i would have to give it some gas and keep the idle up, once the car was warmed up it ran fine

[James Crivellone]

On my 318i the idle control valve never ran right so when i would start the car, i would have to give it some gas and keep the idle up, once the car was warmed up it ran fine

I have tried giving it a little throttle during cranking, does nothing