'88 E30 stops running,..

'88 325. It just died while driving up a hill today. All the dash lights were lit up like you had the key in position one. I pulled over and It started fine and I drove to town. It died again under way and started fine and then ran ok the rest of the day. Also: It usually starts at the touch of a key but 2 or 3 times a week it just cranks and won't start. After a few minutes it starts normally. The other day I started it and got out to do something. When I jumped in and shouted, "let's get this bucket moving, Race!" it died as soon as my ass hit the seat. A previous owners mechanic report states it would die at stop signs and then start easily. No error codes returned but the tach signal was suspected. Jiggling the wires and connectors "solved" the problem but now it is back with me, the new owner. I tested the cam sensor for resistance and it measures exactly as prescribed. The cold start sensor also tested good. If it was a chevy I'd be looking at the bulkhead connector. Any ideas? p.s. I rubbed out the paint and waxed it twice. It looks like a million dollars!

Reply to
cosmo
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Fuel pump relay? Common problem on BMWs of this age.

Reply to
Dave Plowman (News)

Or vapour lock in the fuel lines - notice it happens when the car is hot / stoppped.

Reply to
R. Mark Clayton

Assuming it's injection, this only usually happens when stopped. When running the fuel is whizzed round the circuit quick enough to keep it cool.

Reply to
Dave Plowman (News)

I'd be even more inclined to think a dying fuel pump. I think that is more common at that age than the relay.

Reply to
Bob Smitter

My mechanic ASSURED me that the fuel pumps NEVER failed while at pressure, that they only failed on starting, and therefore stalling out while underway was ALWAYS the fuel pump relay.

Then, after I replaced the fuel pump relay and the car stalled in the middle of Rockville Pike in heavy traffic, not to restart again, I discovered he was wrong.

Next time it stalls out, CAREFULLY disconnect the hose to the regulator and see if huge amounts of fuel squirt out at high pressure. It bet it doesn't. Switch the fuel pump relay with a relay you don't use very much (like the horn) and see if the problem is fixed. Join AAA so you can get towed for free when it turns out to be the fuel pump.

--scott

Reply to
Scott Dorsey

Sorry, my bad. I should have read the whole work sheet. The fuel pump was replaced in august, this year. ($335 plus labor). Also the screen was replaced and the tank cleaned out. Voltage to the pump tested ok. There's no mention of a relay in the report. When I CAREFULLY disconnect the hose to the regulator (on the pump side, right?) I have to have the key on to the second- light up the dash position so the electric pump is still pumping, right? Or are we just looking for residual pressure? Looks like the fuel pump relay is part of a secret auxiliary panel. I will have to find this in daylight. So the theory is the relay fails and opens up, interrupting voltage to the pump and the car runs out of gas. Then after the key has been cycled the relay re-engages and off we go? Thanks again, everyone.

Reply to
cosmo

Fuel pump relay? Common problem on BMWs of this age.

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*Just remember...if the world didn't suck, we'd all fall off*

Dave Plowman snipped-for-privacy@davenoise.co.uk London SW To e-mail, change noise into sound.

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Sounds like a power cable connector is lose at the battery.

Bill in Omaha '86 535i

Reply to
Bill

The relay is under a black plastic cover very near the fuse box. There are probably 3 relays under it.

Reply to
Bob Smitter

Okay, so you know this has been an ongoing issue and it probably wasn't fixed.

First thing to do is HOPE they installed an OEM fuel pump and not a cheap rebuild.

Second thing to do is swap the relay.

No, you're just looking for residual pressure. If you WANT to actually disconnect it while in the on position, you could try that, but it is substantially more dangerous and there should be PLENTY of residual pressure already.

I _think_ on this car the pump relay is clipped to the side of the main fuse panel, and it's the same Bosch SPDT relay as half the other relays in the car so you can swap easily. I am not positive, however.

Right. Alternately, the bearings in the fuel pump are bad or the brushes on the fuel pump are bad.

ANOTHER more rare possibility is the fuel pressure regulator is bad.

Oh yeah, and change the fuel filter if it hasn't been done recently. It won't fix the problem, but it will prevent future ones.

--scott

Reply to
Scott Dorsey

I found the auxiliary relays- they're near the power steering fluid reservoir. Main relay, fuel pump relay and something else. I pulled them all and cleaned up the contacts. There's also an inline fuse associated with the same relay block that had some black tape on it which had turned to goop. When I opened it up the wires were loosely twisted together. I skinned everything and soldered it neatly. I've driven about 100 miles now without any incident. There's a prescribed procedure for testing the regulator; I'm working up the courage. Thanks again, everyone. It's a nut numbing 34 degrees here- boy this car has a great heater.

Reply to
cosmo

Ah - a good Aberdonian like me. Most would just buy new.

Reply to
Dave Plowman (News)

You may have found the problem. I have never seen BMW use inline fuses from the factory. It seems someone has added, modified, or attempted a repair on something.

Reply to
Bob Smitter

I doubt you'll have any future incident. This bit of butchery was almost certainly the source of the problem.

You should know, though, that cleaning the relay contacts will not solve all relay problems; I don't know if the relay springs fail or if I just can't polish the surfaces well enough, but I've never been able to clean these relays and have them work for more than a year or two before failing again. Get a spare relay and keep it in the glove compartment with the spare fuses and lamps.

--scott

Reply to
Scott Dorsey

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