E30 325 died: Grassroots Motorsports forum: Grassroots Motorsports Magazine

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June 17, 2008 9:09 a.m. Gearhead_42 HalfDork

My buddy's new to him 325 died on the way to work this morning

Dunno. I was pulling out of that street by Hot Dog House (was gonna take the "back way" due to the construction) on to 550 and half way through 1st it shut down like I'd turned the key off. Gauges and lights were still alive, but nothing was running the engine.

It turns over but doesn't even come close to catching, except once... after it sat for 5 minutes or so, it turned over, caught, ran for just a second, and died. I almost wish it hadn't caught, would've made it easier to figure out, like it's a coil or fuel pump...

He added that he vaguely remember being able to hear the fuel pump prior to this, but now can not...

Probable culprits?
June 17, 2008 9:12 a.m. therex Dork

Fuel pump is my guess. They die with some regularity.
June 17, 2008 9:25 a.m. Sonic New Reader

The fuel pump relay goes bad more frequently than the pump, and is much cheaper to replace. Try the relay first.

edit: The main relay, which is right next to the fuel pump relay, also goes bad. I just replaced both and it solved an intermittent no start that I had.
June 17, 2008 10:10 a.m. Gearhead_42 HalfDork

Anyone know what "color" the fuel pump relay is? The dealer is telling him they are "indexed by color" and of course he's at work, 10 miles from the car ;-)
June 17, 2008 12:31 p.m. stuart in mn Dork

The fuel pump relay and main relay are the first things to check. I'd also buy replacements for both of them; if one is still good, then he'll have a spare to keep in the glove compartment. On the other hand it could well be a fuel pump. The pump died in my 325ix this winter and it acted exactly the same - it was running just fine, then it just quit as if I turned the key off.
June 17, 2008 1:04 p.m. mad_machine SuperDork

yea, my Ti did the same thing this spring. Only thing I managed to get it to start and run for 5 more minutes... just enough time to get me home
June 17, 2008 1:12 p.m. belteshazzar Dork

jumper
June 18, 2008 7:32 a.m. nasaregistrar Dork

Gearhead_42 wrote: Anyone know what "color" the fuel pump relay is? The dealer is telling him they are "indexed by color" and of course he's at work, 10 miles from the car ;-)
Orange, it is the same one as the o2 sensor heater relay. There are 2 orange ones and a white one on the left inner fender well. The white one is the main relay for the ECU, the fuel pump one is all the way closest to the firewall, swap it with the O2 relay to test.
June 18, 2008 8:26 a.m. confuZion3 Reader

I had the same thing in my Miata. I replaced the pump first. Turned out to be a broken wire. Don't be stupid like me. (The pump was old anyway)
June 18, 2008 8:35 a.m. natefoo None

Gearhead forgot to mention that I've owned this E30 for less than 2 weeks. Huzzah for quality German engineering.

I have 3 relays, one sits lower that the other two and is toward the headlights. According to the manual, that one is the O2 (seems right, since it's the same relay as the middle one, which is supposed to be fuel pump). The 5 prong white one is the closest to the firewall.

I tested both of the orange ones with a 9 volt and got clickage... jumpered the middle (supposedly fuel pump) socket and no start, swapped the orange relays, no start.

I didn't think to test the white ecu relay, I'll have to try that when I get home.

BTW, I don't know for sure that it's the fuel pump. Could still be something else. It just seems likely... I'll have to disconnect a fuel line or something and see if it pumps.
June 18, 2008 8:45 a.m. confuZion3 Reader

When you jumper the fuel-pump relay and turn the ignition key to on, shouldn't the fuel pump turn on? This would be a great way to see what kind of fuel-delivery problem it is (if it is one at all). If you have relay clickage, but no pump runnage, you need to test the pump (and the wiring!!!).
June 18, 2008 8:49 a.m. natefoo New Reader

Yeah... I am pretty sure I could hear the pump before and can't now, even when jumpered.

'Course, now I have to figure out how I'm gonna get under the car on my 15 or 20 degree inclined street. If anyone knows how to accomplish it, it's GRM... any ideas?
June 18, 2008 8:55 a.m. Gearhead_42 HalfDork

Hmmm... you may need to call your "tow company" and have it delivered to the flattest backyard in Bellefonte...

I was just thinking though... the main would power on the pump, so if the main was bad, even jumpered the pump wouldn't run... so test or pick up a new main and a new/spare pump relay, before we resort to under car contortions...
June 18, 2008 9:00 a.m. natefoo New Reader

I'll take G42 Towing Enterprises up on that if I can learn to brake with a tow strap properly.

Okay, got the next thing to test... will report back this evening.
June 18, 2008 10:15 a.m. belteshazzar Dork

How old is the 325? Somewhere around '88 they went to a single fuel pump and it's in the tank. Accessed by removing the rear seat bottom cushion. Very simple job.

You may be grumpy about it failing in under two weeks of ownership, but the poor car ran 20 years before you got it!
June 18, 2008 10:19 a.m. nasaregistrar Dork

exactly what year and model is it? If it is an i car the low relay should be the white ECU relay
June 18, 2008 10:20 a.m. natefoo New Reader

Yeah, '91. And yeah, I was just frustrated (found a few other inspection-failing problems, too).
June 18, 2008 10:30 a.m. belteshazzar Dork

Ah ha.
If the pump gave out a standard issue $100 walbro will drop right in. I haven't seen or heard of any with wiring issues AT the pump on '88+ cars, not to say that couldn't happen I guess.
June 18, 2008 11:44 a.m. natefoo New Reader

nasaregistrar, '91 325i. The low relay is orange, 4 prong like the center one.
June 18, 2008 11:48 a.m. nasaregistrar Dork

natefoo wrote: nasaregistrar, '91 325i. The low relay is orange, 4 prong like the center one.
I will look again at my 90 tonight....
June 18, 2008 12:47 p.m. mad_machine SuperDork

91.. yea, pop the rear seat, you should have a circular access cover. Pull that and the tank and pump should be right there..

Much better than dropping the tank
June 18, 2008 12:49 p.m. belteshazzar Dork

btw, the one on the pass side, not the drivers side.
June 18, 2008 4:19 p.m. mad_machine SuperDork

oops, yes, I should have mentioned that.