Problem - Fuel pumps won't prime, testarossa

I'm hoping Steve or someone else out there has had this problem and knows what the fix is. When I turn the key to on (not run) the fuel pumps always prime the lines. Now I can't get them to prime. I pulled the Tach relay out and jumpered the wires there and the pumps do run. I believe it was #30 and #87. I changed out the tach relay and still no luck. I also have a new fuel pump relay installed in the black box in the rear as well as a new power realy (Fused one). Anything more I can try?

 

The pumps are mounted under the fuel tank, if they are running but no fuel is coming out either the sock filters are plugged or the tank is empty.

 

Thanks, the pumps don't run unless I jumper the tach relay connector. Seems I have another relay/electric problem keeping them from rurning with the key.

 

This is normal -- the US (and late euro) TR fuel pumps do not "prime" when the key is turned to the "on" position and the engine isn't actually running. They only run when the key is in the "start" position or the key is in the "on" position and the 7-12 bank ignition is actually firing.

Please redescribe the operational problem (if any) that you have -- engine fires up OK, and you have spark on both banks, but the engine shuts off a few seconds after releasing the key from "start" to "on", or something else?

Nothing wrong with having a new protection relay (the one with the fuse), but there is no "fuel pump relay installed in the black box in the rear" -- the tachometric relay in the black box is used to control the air pump clutch during cold running, and, although it is similar to the tachometric relay located behind the fuse-relay panel that does control the fuel pump relays, it has different characteristics and has nothing to do with the fuel pumps operation -- nor are the two tachometric relays interchangeable -- i.e., if you found a Durite brand tachometric relay that could be substituted for the Bosch 00280230006 tachometric relay running the fuel pump relays, this same Durite brand tachometric relay must NOT be used in the triangular black box -- it could cause your air injection system to operate during warm-running which would drive the Lambda system crazy. If you have replaced the Bosch 0280230012 tachometric relay in the black box with a Durite one, I would definitely suggest you put the Bosch 0280230012 back in, and, if you are having a hard time finding the Bosch 0280230006 tachometric relay for the fuel pumps, have you tried www.allferrariparts.com?

 

Thanks Steve, maybe I have a hybrid... When I turn the key to accessory position (lights on dash) the fuel pumps always turned on for a second and then turned off. Now the pumps don't turn on for that second before actually cranking anymore. If I tried to start the car the starter motor just turns over and no hint of a actual run is present. Not even a chug. I don't get any fuel smell either when I try to crank. I had definite fuel smell before.

So when you turn your key and don't crank it but the lights on the dash come on, you never hear the fuel pumps turn on for a second?

I also swapped driver's side coil and module and it didn't help.

In regards to the fuel relay in the rear, that F part number on fleabag comes up as a fuel pump relay. The sellers are respected places like this one, at least looks respectable. So I assumed they knew what they were talking about.

http://cgi.ebay.com/ebaymotors/Ferrari-Parts-Fuel-Pump-Relay-Testarossa-NOS-61766300_W0QQcmdZViewItemQQhashZitem5ad2a2352fQQitemZ390080902447QQptZMotorsQ5fCarQ5fTruckQ5fPartsQ5fAccessories

 

Dear Ferraristi,

Mancar, you are describing a symptom...."pumps not priming"

Can you please describing what the problem is.....in detail.

Are you starting the car....it doesn't start? ....it sounds like it's about to start, then dies?


Like 2na said....did you put gas in it?

....only kidding....no really.


Shamile

Freeze....Miami Vice !

 

lol.... I'm trying to start but only the starter is engaging and no other sound is made. Every time I've started her before I always heard the pumps turn on for a second and turn off as I use that as my que she's ready to start. That que is no longer there and the car won't start. It sounds like a sewing machine when I try and start it.

 

Correct -- my fuel pumps don't run at all until the key is turned to the "start" postion.

No argument that they are a respected F place, but, in this case, they have made a mistake IMO. You might call the Bosch 0280230006 a "fuel pump relay" since it is a relay and is (indirectly) involved in running the fuel pumps, but the Bosch 0280230012 is a totally different thing with a different RPM switch point and, I believe, reversed logic -- i.e., on 0280230012, below 4400 RPM, terminal 30 is connected to terminal 87, and above 4400 RPM, they are not connected; whereas, on 0280230006, at zero, or very low, RPM, terminal 30 is not connected to terminal 87, and at any RPM above 0 RPM, terminal 30 is connected to terminal 87. Bottomline -- the tachometric relay behind the fuse-relay panel must be the 0280230006 (or maybe the Durite 0-723-42 that you found in the other thread), and the tachometric relay in the black box must be 0280230012 (and not the Durite 0-723-42). If you meet those conditions, but still have problems, give a shout.

 

Yes, the Durite one I used up front and the correct Bosch I used in rear. Should the car chug on start even with no fuel or just spin the starter over like I'm experiencing?

 

If the starter just spins the engine, but, it doesn't fire up (and you've already confirmed that you do have spark occurring on both banks during the starter motor cranking), I'd suggest that you remove the Durite tachometric relay and use a jumper wire to manually connect the 30 terminal in the relay socket to the 87 terminal in the relay socket -- the fuel pumps should run -- if they do, try starting the engine -- if it does then start/run OK, it becomes a case of confirming/denying if the other input signals are present at the relay socket when the engine is running -- e.g. (when engine is running):

voltage between terminal 15 and ground = +12V DC nominal (would be whatever the alternator is putting out so might be 13~14V DC)

voltage between terminal 15 and terminal 31 = +12V DC nominal

voltage between terminal 1 and terminal 31 = some non-zero value V AC

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If one of the input signals is missing, then restoring that signal becomes the next challenge.

If all of the input signals seem OK, then maybe that Durite really isn't an equivalent, or maybe, it's just a bad one.

If it still doesn't start (when you have the fuel pumps running manually with the jumper in place), that something else entirely.

 

Thanks, I'll have to try that one tomorrow incase it does start. Neighbors.... The jumper definitely turns on the pumps but it was late when I found this out so again didn't try to start it. I'll let you know what I find Steve.

 

I hooked up a timing light to #7 and tried to start. The timing light did not come on and the car sounded light a sewing machine (just starter turning over). I did not hotwire the pumps as I was checking for spark first. Since I changed out the coil and module during this test what can I check next for spark?

 

If you've got no spark occurring on either bank during starter motor cranking (which it sounds like you have -- although wouldn't hurt to confirm/deny that), see post #10 in this thread:

http://ferrarichat.com/forum/showthread.php?t=264265

and the posts that it references for some initial things-to-do/measure/investigate.

 

I sure didn't like this statement. "If those are OK…well, we don’t want to go there …Good Hunting!" Hopefully it won't pertain to me. Thanks Steve going back in.....

 

I resat both connectors under the coolant tank. Still nothing after that. I measured both sensors.

RPM = 685
TDC = 695

I unplugged both sensors and measure them while cranking. Neither had any power.

Whoops, just noticed the sensors need to be plugged in while measuring. How did you do that?

 

Ok, I tried with two small nails in the femail side while touching the head to the male side. All the while trying to get my probes to touch these nails. Still nothing on either. Although it was very hard to do and I can't be 100% sure everything touched. Given neither had power where would I go next?

 

By making a set of small, rigid, male-to-female spade terminal jumpers that gave me a place to connect the multimeter leads while keeping the sensor electrically connected:
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IIRC, I got the small spade terminals at RadioShack, and used some small (bare) busbar I had to connect them (where I clamp the multimeter hook probes).

If your TR has the round ignition diagnostic connector by the LH gas spring mount (mine doesn't), you can also make the measurement for the black TDC sensor there, but you'll need to make some resistance measurements (between the unplugged 2-pin TDC connector in the harness to the round diagnostic connector) to pre-figure out which pin is which (unfortunately, the RPM sensor is not connected to the round diagnostic connector). The "official" tool for making these measurements is the "breakout box" that connects between the 25-pin connector in the harness and the 25-pin connector on the MicroPlex ECU.
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Did you have your multimeter set on Volts AC -- not Volts DC when you made the measurements (although your "nail" connection method is still totally suspect )?

One fairly easy thing that you can do is confirm/deny, with the key "on" (the engine doesn't need to be cranking), if you have +12V DC on the GN (yellow/black) wire in the "y" connector that powers the MicroPlex ignition ECU (and it wouldn't hurt to unplug it, see how it looks, and reseat it). There still might be a break somewhere between the "y" connector and the MicroPlex ignition ECU (so a "good" result here isn't totally conclusive), but a "bad" result here is a definite problem that needs to be fixed. (And it wouldn't hurt to unplug/reseat the 25-pin connector at the MicroPlex ignition ECU also).
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I do have that service plug but I'll have to ohm it out tomorrow. However, the yellow/black wire has NO power with key on. I did pull that connector and it looked perfect. The 7-12 coil solid yellow did but not the far right striped one. Also, the setting I used for volts, there's a red setting with a symbol like this ~ and a black one with a solid black line on top with three dot below it. I used the black one.

Also, the white wire, starter command, third from right has no power when key is on but not cranking. Is position III cranking or just on?

 

This is a definite problem that needs to be fixed. The next place (upstream) to measure is at the AN (light blue/black) wires in the 2nd from the bottom position in the "w" connector with the key "on" as shown in this photo (one of these AN wires comes quasi-directly from the ignition switch "on" position). Here, too, unplug/inspect/reseat the "w" connector:
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The "red setting with a symbol like this ~" is for Volts AC -- use this setting for measuring the flywheel sensor outputs.

The "black one with a solid black line on top" is for Volts DC -- use this setting for measuring the GN and AN wires.

Pos III = cranking. When the key is "on" ( = Pos II), there is no voltage on the B (white) wire.

 

These two wires DO have power.

 

And the GN wire in the y connector still does not have +12V power? Did you inspect the w connector connection? The AN wires could be at +12V with the key "on", but, if the connection from the AN wires to the corresponding male pin on the PWB is bad, the +12V would not reach the GN wires. You can also remove the y connector, and measure directly to the male pin that mates to the GN wires (it may look good optically, but not be good mechanically). If you do have +12V power at the AN wires, but no +12V power on the GN wires (and the connectors/male pins seem OK), it must be a broken trace, or bad solder joint, on the PWB.

As a first test, remove both the y and w connectors and make a resistance measurement from the GN wire male pin to the AN wires male pin = should be near 0 ohms (infinite ohms would be bad)

If you do fail the first test (i.e., no connection on the PWB between the male pins), plug the y and w connector back in and connect an external jumper wire from the AN wires directly to the GN wire (this is what the connectors/male pins/PWB is supposed to do -- i.e., the PWB male pin at the AN wires should be directly connected to the PWB male pin at the GN wire) and see if that restores spark during cranking.

 

Had a hard time getting a constant reading but the one that popped up the most was .3 when set to 200 ohm on my multimeter. No other Ohm setting registered a number. This is if I use the sides of the male pins. If I use the tips of the male pins I can't get a reading. I'll try the jumper. Just got to figure out how to make a jumper work while the plugs are in place.

 

0.3 ohms, or even 0.5 ohms, would be A-OK -- if you just touch the two multimeter probes directly together you might get 0.3 ohms as a result. However, if the resistance is 0.5 ohms, and the AN wires are at +12V, the GN wire should also be at +12V.

 

With the jumper in place the car started up like a brand new car.... OMG!! What do you recommend as a good fix? I'm not comfortable with playing with the circuit board but I can tie the two wires together with solder. Any problems with that?

STEVE is the MAN!!

 

Glad to hear that you've identified the (real ) problem. Your resistance measurements between the male pins seems to indicate they may just have a surface oxide film that is preventing good contact with the female tongs so you could try refreshing their surfaces with some fine sandpaper (even though that removes the original plating). It is a little surprising that the PWB and/or solder joints would have a problem/damage yet the female contact(s) show no thermal damage. Nothing wrong with adding the external jumper in a more permanent fashion, but use a fairly large wire size -- the stock GN wire size of 2.5 mm^2 translates to (the unobtainable) 13 gauge, but 14 gauge would probably be plenty OK since it isn't a long wire run (as, of course, would be the larger 12 gauge).

Happy Motoring!

PS If you ever hear your fuel pumps prime...