328 Will Not Start

From where you sit, put a volt meter across the fuel pump. If you have 12 volts and no pump operation, you have a bad pump. If you don't have voltage across the fuel pump, you can disconnect the car wiring and apply an independent 12 volt supply to verify that the pump runs.

If you look at jim (gatsby)'s link, you'll see that the pump and accumulator are mounted on a triangular plate. You could remove that plate if you're having trouble reaching the electrical connectors.

But you need to track down why there isn't voltage from the car, if there should be.

Is anything coming on with the ignition? E.g. Fuel gauge?

When you turn the key to "on", both relays "u" and "s" should activate. In a quiet garage, you'll hear them click. In a noisy garage, you can feel them activate, if you place a finger on them. (Be advised - they get warm.)

When you turn the key to "start", that runs power through relay "s" to activate relay "r" which powers the fuel pump. When the car begins to injest air, the AFM plate moves off its rest position, opening the safety switch. That deactivates relay "s", and ignition power (from relay "u") holds relay "r" active. If the car stalls, the AFM plate returns to rest, activating relay "s" and cutting off power to the fuel pump relay "r" until you hit the starter again.

If you turn the key to "on" and press on the AFM plate, relay "s" should click off and relay "r" should click on ... and the fuel pump should run.

If none of the relays are operating, you might have a connector problem right at the relay board.

A continuity meter by itself isn't going to help, here. You need a volt meter to look for voltage switched on at the appropriate times.

By "washington", do you mean DC or state?

 

Russ:
Because the relays seem to be clicking, it sounds like the system "may" be working and the pump may be bad. At this point, I would apply 12V directly to the fuel pump if the pump runs then you will need to look upstream.

Mark

 

Well, that makes it a tad harder for me to drive over (from VA) with a meter and power supply.

Actually, it should be both.

Your next step would be to pull the blue safety switch connector, turn on the ignition, and check for 12 volts across the fuel pump itself. (Some Radio Shack jumper "test leads" might be handy for connecting the meter to the pump terminals.)

If you have voltage across the pump, but it doesn't run, then there's something wrong with the pump. Otherwise, there's a problem getting voltage from the relay to the pump -- a wiring or connector issue.

 

Russ -- Do you have a copy of Fig 2 from the '89 328 wiring diagram from Steve Jenkin's site? My comments will use some of those names/labels.

Remove relay r and confirm that there is always +12V (relative to ground) on the terminal 30 female socket (even with the key "off").

If not, indicates something wrong with the PWB itself and/or fuse/fuse holder.

If OK, jump the "r" relay socket 30-to-87, and measure the voltage from the large P (beige) wire in the w connector on the left side of the fuse/relay panel (4th from the top) to ground. Leave the w connector plugged in for this measurement -- just touch one meter probe to the metal terminal holding the large beige wire and the other to a decent ground (but it wouldn't hurt to remove/inspect/reseat the w connector first).

If this is OK when relay r is jumpered (i.e., it measures +12V), but the large (P) beige wire at the fuel pump is still not at +12V relative to ground, there is another connector 144 behind the passenger footrest that the large P beige wire passes thru -- you'd measure/inspect there next (you should be able to identify it just by size/color).

Those are all of the connections that are shown on the schematic, so if you've really got +12V at the relay r socket available, you must have a break somewhere if you don't get +12V at the fuel pump with the relay r socket jumpered 30-to-87.

 

Russ -- I have to say your "story" seems to be meandering all over the place

If the fuse is not blown, there will always be +12V on terminal 30 at relay r (regardless of key "on" or key "off").

Since the 15A fuse blew, you should replace the fuse with a new one, unhook the P beige wire from the fuel pump, and try jumping the relay r 30-to-87 again:

If the fuse still blows, you have a short in the wiring or PWB somewhere.

If the fuse now doesn't blow (when you add the 30-to-87 jumper at relay r), measure the voltage at the (loose) P beige wire you unhooked from the fuel pump relative to ground. If it is now at +12V relative to ground, touch it back onto the "+" fuel pump post -- if the fuse blows and the pump doesn't run, you can be fairly sure the pump electric motor is bad and/or frozen.

I've never directly fondled the w connector on a 328, but IME all similar F connectors are unpluggable/repluggable if you "open" whatever mechanical retaining clips/features are present.

Sigh...I was hoping this wouldn't take 30+ posts as all of DGS's posts were perfectly on-target...

 

Russ -- I forgot to add that since you now report a fuse blowing would you please double-check that relay s is a ...101 relay and relay r is a ...113 relay (sometime in all the swapping this can get messed up).

 

Sorry if I was a little gruff earlier Russ -- sounds like you've got it surrounded now

Although I can't yet understand how an "open" beige wire to the fuel pump would cause the fuse to blow when jumpering relay r? If the fuse was going to blow with relay r jumpered, it should blow when the safety switch is unplugged and the key is "on" (which "closes" relay r and does the same thing as the jumper -- hooks 30-to-87).

 

How'd the connector on the fuse block look? Any discoloration on the connector shell? (15A is a lot of current for those connectors).

You'll want to see if you have voltage on both sides of the connector behind the footwell. If you have voltage there, but not at the pump, you'll have to trace the wiring harness between the two.

If it's not a connector, you might also want to check the garage space for rodent sign.

Jumpering a Bosch relay socket with a bare wire can be tricky -- and the fuse panel being "hot" with the key off catches people out.

 

You can't go through the forward well -- there's a structural plate between.

You peel back the carpet on the pass side. There are four large screws on either side of the panel, straddling the velcro strip that holds the carpet. Peel back the plastic liner at the bottom and you'll see two more large screws.

In all, there are six screws, three on either side. Then the panel comes off.

You might have to maneuver around the side carpet and the center leather covered kick plate to get to the other side, but the panel should be loose when you remove the six screws.

As I don't think there's room under that panel for a stereo amp, I'm presuming it was mounted on the upper side? That may be masking some of the panel mounting screws.

---
Failure is not an option -- it comes bundled with XP

 

Sounds like a bad crank sensor

 

I know this is an old thread but the information helped me big time so I thought I'd add some more detail for the next guy trying to figure out why his fuel pump doesn't run:

Ok, Did everything mentioned in this thread and still no juice at the fuel pump. Got some additional tips from this thread( very good) http://www.ferrarichat.com/forum/sho...ump+328&page=2 I removed relay "U" and jumpered 87 to 30 and still nothing at the pump. Went to Ferrari.jenkins.org and looked at the wiring diagrams online. Found I had 12v on connector "W" which is a vertical conector on the left side of the fuse panel and probed the 4th one down(biege) and had 12v there with relay "U" jumpered. Looked for the next connector in the wiring diagram which was connector 144 located behind the panel in the passenger footwell. It is one of the two attached to the car not the back of the panel. As soon as I tried to push my meter probe into the beige wire in the lower left the pump started to run. Figured I'd document my journey and pay it forward for the next guy in honor of those who posted the tips that got me started in the right direction. Also found my clutch cable is starting to fray while I was under there. Thanks again for the help. I can post some pics of connectors if anyone thinks its worth the trouble.

 

Here are pics of the connectors and locations. Notice the discolored connector. Measured Amp draw on pump and got a little over 7 amps. I imagine this is a common problem. Not sure what the best fix is. I cleaned the contact as best I could and put a tiny bit of grease on it before putting it back together.
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Just posting something here to keep this from getting deleted for being too old.

 

Great pics... this was the source of my problem as well... infuriating... I had a wire spliced in with a fuse... since then no problems. I am betting this is your issue.

Tom

 

Bump!

 

13 years later I just encountered the exact same thing as Kevin, trying to debug the whole thing and got to the "testing voltages at all the contacts" part, as soon as I pushed the test probe on to the beige brown wire on connector "W" the fuel pump spun up. Now I just have to figure out how to get it to stay on with out the probe jammed in there lol

 

Thank you all so much for documenting all of this - my 2nd day with '88 GTS