hello again--fuel system basic help for '82 320i needed

[spelbynder]

Hi again--haven't been here for months but I'm back.
I'm learning how to fix my car one problem at a time & I haven't had to deal with fuel pumps and relays yet, so I'm looking for some very basic info.

I'd been driving the car for several days after it sitting for a few months. One morning it fired right up, ran for a few seconds, then died.

it cranks fine but it's getting no fuel. I'm not smelling gas, so I don't think I'm flooding it or have a problem getting spark.

After searching the archives, I think my prob is no power to the fuel pump. when I turn on the key, there's no sound of it working, just silence. replaced old fuel pump fuse--nothing. tried whacking the pump, that didn't work. switched out the pump relay in the fuse box--nothing. I believe if the fuel filter was clogged, I'd still hear the pump working, I just wouldn't get fuel.

I'm trying to rule out everything else before investing in a fuel pump. How do you check if it's getting power?

What else can I check before assuming it's the pump? I read that someone took the fuel line off the pump outlet to see if fuel squirted out when they turned on the key. Would there be a point to that if I don't hear the pump working?

Thanks a bunch. I appreciate your help.

 

[epj3]

Have you actually TESTED for spark? It's even easier to check for spark than for fuel delivery. Check for spark, and if you have spark go from there. If not, then it is most likely the distributor cap and rotor. I have a feeling letting it sit for months allowed water to get into the distributor cap. Definitely tear apart the electronics before messing with the expensive fuel pump and injectors.

 

[Kirby]

If you're not sure about the fuel pump, the standard way to check it quickly is to open the fuel line at the pump or at the engine.

 

[ldzpstnr]

Make sure you dont have any vacuum leaks, I doubt you do though.

Those 83 and earlier 320i's had the L-Jetronic fuel injection system I believe, while the 84-85 318i had the L-jetronic. I THINK, its been 5 years since I tinkered with a 320i. If you end up needing any intake manifold parts, I have a complete(i think) intake manifold for '78 320 including throttle body.

The K fuel system is mainly a mechanical one, and if there are any vacuum leaks it will confuse the simple computer and mess it all up. Just make sure vacuum lines, intake boots, and the air cleaner are all (grammer) hooked up properly.

Can you check and see if the fuel pump connector is getting voltage WHILE you crank over the engine? My fuel mump on my '87 325 doesnt run until the motor starts... i think it gets initial voltage when you hit the starter.

Good luck, Aaron