Starting problems the dreaded melted fuel pump connection

Hi all,

Been having starting problems again on my 3.2. Previously I narrowed it down to the fuel pump relays R and S in the fusebox and i fixed it by removing them and putting them back in. It worked well and started better than ever.

On the weekend it would not start when hot after i had been driving for a while. It seems to be random and also did not start when cold but much worse when hot.

I bought the new plastic Bosch relays from Ferrari and replaced the old ones and still did not work. I put the old ones back in and was ok .... for a while!

I still have the old ones in and i noticed tonight that the large white connector on the right side of the fusebox has melted on the 3rd connection up from the bottom - see photo. I believe this is for the fuel pump and have read in some posts that this is a common problem.

Has anyone had this and fixed it successfully? Am i right that this is where my non-starting problem lies?

Thanks very much.

Peter
View attachment Mondial_32_fusebox.pdf

 

Photo attached
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Hi Peter,
I had the same problem, in my case the white connector was burned so badly at the fuel pump and ac connections that it became brittle and started breaking apart, so I changed the connectors to standard .187 size female slide connectors (picture 1), that worked very well for a while, but as you know our car now won’t start again. It also became difficult to plug the rest of the white connector after changing the fuel pump and ac connectors (picture 2), so eventually I removed the whole thing and installed female slide connectors for all the connections (picture 3), they are working perfectly, all the systems work, except for the fact that the car will not start again, but I don’t think that is because of the connectors at this point. I used pictures of the original connector to make sure I plugged all the wired in the correct spot. I hope this helps.
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Thanks that's very interesting.

We have the same exact problem again. Today I started it from cold and would not start at all. It cranks very strongly but just won't fire up. I tried my little trick again that worked before. I removed the fuel pump relay (marked R in the handbook) then put it back in and it started and fired perfectly. I drove it for 2 hours and got it well warmed up turned it off and restarted it immediately and no problem. A few times I would turn it off and wait a while then restart and again was ok. It was flawless and performed remarkably.

It always seems to start when I remove that fuel pump relay and replace it. Try this and see what happens, will only take a minute.

Still not sure what the root of the problem unless it's the white connector that needs to be changed but why did it melt and how can I prevent it from happening again or getting worse.

Does anyone know where they can be bought from?
Thanks.

 

Peter, if I had to guess, it kind of points to your fuse box, look for burn marks on it. From what you have told us, it restarts everytime you take out the fuse and pop it back in but the car does not start after its been driven for a while. But starts again after cooling off. points to ----> Fuse box over heating, and works again after cooling off sometimes. But honestly, I'm no mechanic, just good at troubleshooting and paying attention to details. You can try searching this board for anyone who has successfully rebuild their fuse box.

The wire connector from/to fuel pump with the burn mark obviously heated up due to a short circuit, possibly from the fuse box source -either fuse or connecting soldering on fuse box. They do go bad on these cars all the time. Keep troubleshooting, you'll find the root cause of a bad connection problem or short eventually. Worst case, I think a new fuse box would definitely fix the problem but will cost you.


~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Source #1 for new fuse box I found:
electrotech
Hi Guys, I wanted to introduce myself. I am Electrotech and have been an Aerospace electronic technician for 25 years involved in cockpit electronics for commercial airlines. We build and test the electronics racks for the Boeing, Airbus and McDonald Douglas airplanes. Two years ago our local Ferrari parts distributor asked me to come up with a drop-in replacement for the 1983 and newer Mondials. These cars were plagued with electrical problems from the relay\fuse box. After looking at the damage on several of the fuse boxes it became obvious that the (5) thin (0.015 thick) Mylar boards did not have the strength to hold the pins in place and did not have the current capabilities for the starter, fuel pump and fans. After 2 years, 4 programming engineers and 3 board fabrication houses, I have a circuit board that I am pleased with. This new board is a single board with internal layers that will replace those thin (5) Mylar boards. The new board is heavy duty with 0.125 thickness (normal is 0.062) and 2 oz copper circuitry (normal is 1 oz). The Mondial boards performed so well in the field that I now have replacement boards for the 1985-1991 Testarossa and most recently the 400i models. I am now confident enough to offer a service to Ferrari owners of replacing the old relay\fuse box Mylar cards with the new replacement card. For $850+shipping I will remove the old cards, install the upgraded card, test it and return within 3 days. I would like to eventually stock completed assemblies so if anyone out there has broken fuse boxes sitting around, I’ll make a deal with you for these cores.
Best Regards,
Electrotech
Phoenix, Arizona

Have a 1983 & newer Mondial with electrical problems? Upgrade your fuse\relay box with a new single 5 layer circuit board.Fast turnaround.Not sure if your fuse\relay box is the source of your electrical problems? Send it in for diagnostic testing. Board circuitry and box performance tested on a Mondial testing fixture.Board upgrade $850+shipping. Diagnostic testing $250+shipping. Email [email protected]


Source #2 ZERTEC was working on a new design fuse box.
http://www.ferrarichat.com/forum/mondial/163273-new-mondial-fusebox-done.html


Source #3 Birdman site
http://www.birdmanferrari.com/fusebox_upgrade.htm

 

Thanks Mike, appreciate your advice as always!

To clarify, its not the fuse that i remove and replace to get it working, its the fuel pump relay (marked R in the handbook for our 3.2). The fuse has always been ok and never blown. I removed it to check it and the fuse holder on the board is ok, no burns at all. The only visible problem is the burnt and melted long white vertical connector at the right side of the fuse box at the fuel pump pin connection point as in my photo above.

The starting issue is random. Today i started it for first the time since the weekend and it cranked very strongly but would not fire up. Therefore it also happens when cold. Previously it also happened when hot. Thats why today, after i removed the relay and put it back and got it started perfectly, I drove around for miles and got it to full operating temperature then turned it off and restarted it again and was perfect. I tried this a few times from an immediate restart and also by waiting for a while, and was perfect. I was testing to see if it would start when hot and it did ... this time

I have just spent the last 2 hours going through old threads and youre right that a new fusebox would be ideal but at quite a cost.

I discovered many other threads going back almost 10 years where people have complained about the exact same starting problems and there seems to be 3 options:

1. New fusebox.

2. New vertical white plastic connector (and the female connectors)

3. To bypass this bad connection with a bayonet wire connection.

It seems that the resistance build up at that connection point and the huge current simply is too much for it to handle and gradually melts away over time.

not sure where i can get that block and the female connectors but i reckon that will be my first port of call.

Is it easy to remove the complete fuse box to check the circuit board behind? Just worried about disturbing everything else that is currently working ok.

Thanks very much.

Peter

 

Mike cites Electrotech here:

$850 sounds quite fair to me.

Jonathan's kit is for the 308 (and 512BB) fuseblock inside the car... not found in Mondial.

I just got home and saw this thread. I can add a little (I used to work as an engineer in the electrical connector industry - 30 years ago - yes, it's been awhile).

With regard to the fuseblock, here's what I believe happens in these things:

The fuseblock contains a number of soldered connections that are subjected to thermal cycling and vibration. It is probably correct to think of the relays as masses hanging on the end of lever arms; coupling mechanical forces into the solder joints as they vibrate. A bundle of wires also puts a mechanical load on its associated connectors and couples vibration into them and the solder joints.

Now imagine that you get a hairline fracture in the solder joint where the traces on the board are joined to connector or relay pin. Now you have a poorer quality electrical connection, the resistance is a little higher than a well-soldered joint, and a little more power is being dissipated at the connection. Things are probably still OK. Add more vibration, a little atmospheric corrosion of the surfaces in the fracture region, some thermal cycling and the resistance may really start to go up. A few things can happen:

1. You might get an intermittent circuit, it might only work when cold or hot, or when the relay is reinserted in the socket, mechanically forcing the connection back together for awhile. You might have an enlarged gap where the solder is no longer making reliable contact in this scenario.

2. It might no longer make contact and just go "open circuit". Probably the safest failure mode as it will simply stop conducting.

3. It may continue to work with a high-resistance connection. In this case, there may be a lot of power dissipated in the area of the solder joint, and there's not a lot of metal in there to act as a heat sink and safely spread the heat around. So even a few watts will show significant heating effects. So now you see temperatures high enough to melt solder, burn or melt the substrate, etc.

4. Call the fire brigade! (OK, probably not too likely, just had to throw it in.)

So what can we infer from this? Well, anything we can do to lower the current flowing through the wires, relays, fuses, connectors and board is a good thing. Making things more mechanically rigid will probably help, so that relative movement is constrained. Getting some cooling airflow in there will help. But repairs must be made first.

Considering the idea of lowering current: Probably the least expensive repair that has a chance of becoming a long term fix is to get the fuel pump wiring off of the board as much as possible, using an external relay to handle the current the fuel pump draws. (I think the pumps are spec'd at about 10A continuous draw when in operation.) In this way you get the high current to the pump away from the board, and you can build things to a higher standard. This will take time and effort but not a pile of money. And assuming the rest of the unit is OK, you should be good for awhile. Purists will correctly point out that it's not original. And you're execution has to be really good to make it work right. Ideally, other high current loads should also be handled elsewhere, but at some point outright replacement will be a better solution then this piecemeal approach.

If you intend to repair the fuseblock, then I would re-terminate the connector where the melting is observed, replace the plastic connector body, etc. There was a thread in some section here about the part numbers for the plastic connector shells and pins, they're not too hard to find.

It isn't hard to remove the whole assembly and inspect it. If you work carefully and don't try to force things and avoid straining wires you should be safe. I've done this without incident. The damage is probably internal, however...

If you open it up you'll find a stack of flex circuit boards which collectively act in the same way that a modern multilayer board works. The pins that the relay terminals fit into are soldered to one or more layers, as are the fuse terminals and connector terminals. If you decide to tackle this, you'll need a desoldering tool, and you'll be removing one layer from the stack at a time 'til you get it disassembled. You can then make repairs. Some folks have added wire at this stage, in an effort to increase the current handling capability of the existing traces on the boards. Then you reassemble things one layer at a time, soldering where appropriate at each stage. A good "while you're in there" thing would be to replace every termination. Did I succeed in conveying a sense of tedium?

So yeah, it looks like your choices of buying a new unit or bypassing the bad connection are reasonable. Bypassing may only be a partial solution if there's other damage. Repairing the damaged connector may only be a partial solution if there's internal damage to the fuseblock itself. Personally, I'd try to use an external relay/circuit for the fuel pump or, if cost was no concern, buy a modern replacement and be done with it.

Sorry, probably not too helpful. But I think my reasoning regarding the failure mode is mostly correct.

 

Hi Charles thats fantastic.

Thanks so much for your detailed response especially from an engineer's point of view.

From reading what you wrote and with my personal capabilities I will first try and replace the white connector with a new one together with the 10 metal female connections on the wires that go into each receptacle. As you mentioned it could be the the weakening of the connection withIn the white connector that has gradually worked its way to increase resistance at that point of contact which in turn increases heat at that particular point.

With that in mind it makes sense to try that first as there is no other problem anywhere else which may suggest anything other than those new components. I really don't feel too confident in removing the fuse board and having the circuit board fall apart in my hands by disturbing after 25 years, or for me messing it up when I put it all back together

I will be ordering the parts and update once it's all done.

Thanks again it's all been very helpful!

Peter

 

Finally, i received the new white fuse block connector and some connector pins to replace the burnt out one in the fusebox.

I was having starting problems, whether hot or cold start and narrowed to down to the culprit of the fuel pump connection wire that melted in the white connector block.

Didnt take long at all and was very easy to do. As a precaution i soldered all the wires in the block to their pins so there is no possibility of loose connections any more.

Since i did this it has been flawless and starts instantly every time now, no continuous cranking.

I also replaced both fuel pump relays marked R and S in the handbook (3.2 Mondial only).

So far so good. It starts and goes very strongly now.
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That's great... hopefully that's the fix.

I resolved my intermittent "no crank" issues last year or so. Recently, the a/c system started acting up (burning wires/connector and over-heating relay) so I got tired on the poor original design; sent it to Dave Helms for an upgrade.

Same as on Ted's Mondial t.

http://www.ferrarichat.com/forum/142162518-post3.html

 

Thanks, like you said hopefully that's the fix.

I will keep an eye on that connector block to make sure it doesn't melt again. I got the connector block for about $6 and the pins for about $2 each, all directly from Ferrari themselves.

 

That fuel pump connector is a common fault. I tried ordering oem replacements from major supply house and was told don't bother it was an issue with many 80s F cars under warranty is best to use that pin to signal a relay to connect direct source of power. Another issue I found when chasing this is there is an as yet unlocated fuel pressure leak down--with pump running takes a fair amount of cranking to get it to start, particularly when warm. I have it narrowed to the pressure regulator i the CIS or a fuel injector. Holding throttle on the floor while cranking minimizes the cranking time but it is still long.

Mine is a 1982 Mondial 8 with the GT Car Parts upgraded relay and fuse board.

 

Hi, is the pressure regulator an easy component to replace? Where exactly would I find it? Any improvement is a good one even through I may not need it just yet.

Thanks.

 

Hi Peter, I believe your car is the euro CH87 version, so this diagram should apply. US cars have a different setup as Steve Magnusson has mentioned below in another thread:

"I believe some of what he's talking about ("injection sistem is different") only applies in Europe (to both 328 and 3.2 Mondial) when they came out with the CH version -- i.e., circa 1987, pulse air injection and a cat were added to the K-Jetronic without Lambda system (often identified as CH87 or C7), and, then in 1988, the CH version went to the KE3-Jetronic with Lambda system (CH88 or C8). Doesn't apply to US version 328/3.2 Mondial (which are all K-Jetronic with Lambda plus pulse air injection plus cat)."

happy hunting...

FYI, for the US spec cars, this is a great thread to read: http://ferrari.cdyn.com/carl_rose_docs/Ferrari%20328%20CIS%20Fuel%20Pressure%20Check%20with%20Pixs.pdf
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Thanks Mike, mine has no cat. I experimented a bit today too see if I may need the pressure regulator. I have a day off (never work on my birthday) and the cabin fever was getting too much and no rain for a change so I thought I would test out a few things. I haven't really driven it to warm up properly since I rewired the new connector block that was causing me starting problems from the melted fuel pump connection.

I started her up from stone cold and was instant, then let her warm up for about 15-20 mins before driving at which point the 2 radiator cooling fans came on which was the first thing I wanted to check was working. Then went and put approx $50 of Shell V Power and just drove everywhere. Every now and then I would stop then re start to check it would fire up the same as it did when cold, again no issues. About 2 hours later of hard driving and almost every drop of fuel used it was totally flawless and pulled like a train, no issues at all. The engine and all components were all at operating temperatures and amazing.

Looks like the rewiring of the melted connector block was the problem solved. (Until next time!)

Cheers.

 

Well done Peter, that's Fantastic! -carry on mate!

CHEERS from America on your birthday!!!

 

Thanks Mike, appreciate that!

Happy motoring to everyone!

 

Congratulations on getting the car fixed!

Happy Birthday from across the pond.

 

Thanks Robogeeks. By the way did you manage to fix yours, does it start ok now?

 

It started this past weekend. It made our Sunday. The car is not consistent. It had not started since January.

We replaced the battery, relays, fusebox board, and sparkplugs. We bypassed the white connector. We checked all the fuses and verified that the fuel pump runs.

There is a great mechanic in the area, and we are waiting for him to have some time to check the car out.

 

That's great to hear you have someone to check it over.

Do keep up posted as to what the diagnosis is when you find out.

All the best.

 

Dave Helms upgrade my fusebox and I'm almost finished with the re-installation.
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Hey Peter,

I had the exact same problem when I bought my Mondial. I had to change out the whole fuse box. Your shots could have been taken in my car!
I was also having a problem with the car dying out on me during really hot days, that was traced back to a problem with the fuel pump.
I presume when it was really hot outside the pump would draw to the point of melting the connector the cutout...
No problems since...

Regards,
Mario

 

Hi Mario,

Great to hear you sorted the problem out. It's also good news that these are all known problems and easily dealt with and with so many experts here on F chat it makes ownership more enjoyable.

There's always something that needs doing and that melting fuse box connector seems to be catchIng us all out

Cheers.

 

I went to Autozone and got some connectors. They are too wide to fit into slot??? Is there a special size you need?
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