Running stupid rich 325e

[alanhigh]

I have a 1984 325e that I just picked up, and it runs like shit seemingly randomly. I have replaced the coolant temperature sensor, tested the AFM, the idle control valve, and the throttle position switch. They all seem to be good, the CTS was out of range but it has a brand new one in it now.

Basically, it just runs really rich and has no power, and refuses to idle without dying. The problem is that it's totally intermittant, and I can't really replicate the problem because sometimes it will do it on cold starts, sometimes not, sometimes it will do it when driving and go way, sometimes it won't happen at all.

I don't know where else to go from here besides tracking the wires to see if they are frayed/bad and replacing the ECU.

Previously it had a bad thermostat, and was just idled all fo the time and driven while cold, so I assume it still has an assload of carbon built up.

Any ideas?

[E30_fiend]

three words



Crank



Position



Sensor

[alanhigh]

cps

Really? I would not have thought that the crank position sensor would cause those kinds of problems. I guess I will replace that next.

[alanhigh]

Really? I would not have thought that the crank position sensor would cause those kinds of problems. I guess I will replace that next.

Ok, now this is motronic 1.0 and from baseline investigation it seems that there might be two crank position sensors. Is that true, and if that is, which one will be the one I need to replace? I believe there is one on the front of the engine, or is it in the bellhousing?

[dashboardmonkey]

Both are on the bell housing.....replace both

[Dag]

My car is doin' the exact same thing.

How hard is it to replace those CPS's?

[alanhigh]

My car is doin' the exact same thing.

How hard is it to replace those CPS's?

Mine seem to be on the drivers side bellhousing right, easily accessible. I haven't looked any further than that to see where they plug in however. I assume it won't be too terribly difficult to do, I juts want to make sure that I get it done before we get another 4in of snow and I have to drive on my yokohamas.

[Dag]

Mines an 86, not sure if that makes a difference.

[Faviolosky]

my 325 e did the same excact thing, i changed everything except the fuel pressure regulator, after i did that the car ran like a dream

[EvoStevo]

Is the Crankshaft position sensor the same as the engine speed reference sensor? Whatever it was I replaced, it was in the front of my 'i' motor.

[jlevie]

In this case I'd suspect a fuel delivery problem (bad FPR, block return line, etc) before a CPS. Run the fuel tests to see if the problem is in the fuel system.

[alanhigh]

I'm resurrecting this thread.

I've replaced AFM, TPS, FPR(but it may be from an I, I need to check part #s again), ICV + ICV computer thing(a green one), O2 sensor. It now will idle, but it seems like its missing and its still running stupidly rich, seemingly randomly. I've let the car sit for a couple days and come back to it, and it runs great for about 30 miles, and then just kind of falls on its face. Or if I start it up, turn it off, and start it up again.

It will idle, barely. Anything below 1500 RPM it just kind of falls on it's face though. Above 1500, it works fine.

When it's not running rich, it runs beautifully.

[alanhigh]

In addition, the fuel pump whines. I don't know what that means, but it definitely is while sitting there idling. I can't hear it any other time.

[twright]

My external fuel pump whined when the internal (in tank) fuel pump was dead.

[884door]

Cracked intake tube? It's happened on pretty much every older bmw I've seen and it will make your car randomly run shitty. This probably wont solve all of your problems but it may be part of it...