Car won't start

I've got a 99 550 that won't stay started. It does intermittently start and run for a few seconds and then stops.

My problems started several months ago - got a slow down light. Looked into this forum and found that many times this is related to a bad convertor temp ECU (can't remember what it is called). Car was running - kind of - not much power - could have been running on one bank not sure. Anyway I changed out both ECU's and thermocouples and the battery, since it was getting old and I did not want to worry about that. Somewhere in there the car stopped starting.

I did some more research re how a nonop fuel pump might cause a slow down light. Read the pump pressures on the rails - one was zero and the other was really low. I then pulled the fuel pumps - and found lots of disintegrating black rubber and the return line on one pump was broken. So I repaired the fuel pumps (replaced many parts including the basic pumps) and replaced the filters. Both now give 60psi on the rail when hot wired and 50psi connected and run as normal. The car now at least intermittently tried to start - would go for a few seconds and shut down. In the mean time I ordered and changed out all relays (I've had the car for several years and had never changed a relay so I needed to do it anyway)- no change. Today I ran both fuel pumps directly off the battery and tried to start the car - wondering if their current draw was causing an issue - no change - would intermittently try to start for a few seconds. Another thing I did which I found interesting was when I electrically disconnected the fuel pumps (with pressure in the rails at 50+ PSI) and started the car the fuel pressure did not change. That indicates to me that the injectors are nonop. I'm wondering if that is a valid test.

The car is doing other screwy things. It has about 1/4 tank of gas in it (90% new btw). Several times I've gotten a fuel tank with a line though it on my display - and at the same time the gas gauge shows zero. Most times though I don't see that and the gas gauge shows about 1/4 full. When the car does fire for a few seconds - if I try to start it immediately again it will not fire - but many times it will if I let it sit for a few hours.

So about now I done a lot of things that needed to be done anyway - and still have an issue. When I pull the OBD codes I get a P1146 and P0600. The P1446 I assume is related to the slow done light. The P0600 is apparently due to some kind of ECU com issue which could be related to what I am seeing. I'm thinking that my original problem was likely due to a lack of fuel pressure. I'm not sure what I am dealing with now. I've not checked for any kind of spark (yet) and am tending to think that maybe the next thing to do is to sort out if the injectors are operating properly. That fact that it starts for a few seconds - sometimes -has me thinking that at least at the start the injectors and plugs are operating - so what would cause one of them to turn off? The car seems to be behaving differently at different times which is also problematic. So before I went any farther I thought I would check to see if anyone has any ideas?

 

It could be that the Right Motronic ECU is not talking to the Left ECU. When the Immobiliser ECU unlocks the R ECU, the R ECU sends a signal to the L ECU to unlock that. I can't remember if the immobiliser affects both fuel injectors and spark on the 550 (?). Anyway, it might be good to check for spark so we can narrow things down.

If you've changed both thermocouples and the thermocouple ECUs for the P1446 code, all that leaves is faulty wiring from the ECUs to the Motronic ECUs or internal Motronic ECU issues. Whether this will stop a cold engine starting, I don' t know.

Do you know how old your crank sensors are? During cranking, the ECU commands all injectors to fire simultaneously to get things up and running (after seeing at least a 30rpm signal from the crank sensors). Could it be that the signals are not strong enough to get a good reading from the crank sensors for proper timing, but sufficient to get some kind of combustion briefly?

Sorry, nothing really jumps out at me at the moment.

 

Got starter spray? Go to automatically store and get some. When car starts you said runs for few seconds. If you spray starter spray into the intake and car runs you got your answer. You still got fueling problem

 

Where do you spray it on these cars, BillyBob? It's not like the old days where you can squirt some starter fluid directly in the carbs. Even after the MAFs, it has a long way to travel horizontally into the individual throttle bodies.

 

Open hood see 2 holes where air goes in. We are not driving to supermarket. We are just running g car on unmetered mixture of air with something that goes bang.

 

FBB, Qavion has an F355.

Here are the 2 holes in the 550, Ian...


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He gives a good differential diagnosis of no start causes.

 

And the holes go to the paper (?) airfilters, MAFs, throttle bodies, etc....

I just heard that ether-based products melt certain types of plastic

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Ferrari plastic dissolves by itself...AKA sticky interiors...

 

I'm still chasing this. Image Unavailable, Please Login Image Unavailable, Please Login Image Unavailable, Please Login I've acquired a Galileo and - at least somewhat learned how to use it. As some more background if the car has been left alone for a while - it will start for about 2 seconds and then shut down. I pulled the connector on the no1 cylinder. One pin always has 12 volts as it should. I connected up a noid light. The ling blinks for the two seconds the engine is running and then shuts off. If I try to restart the engine right then it turns over but does not start and the noid light never blinks. Ok so that tells me that ECU is not putting out pulses as it should. BTW yes when I use starter fluid I can get the engine to fire.

So I started to interrogate the ECUs to see what I could find. Image one shows the output of errors from the instrument cluster ECU (this is after I cleared the old data). It seems to indicate that something is messed up with the inertia switch. The inertia switch in the car is new and untripped - so something is weird here. The next image is a list of values I pulled from the instrument cluster ECU. You can see here that state of the inertia switch is off??? Also the fuel level is wrong. The tank is 1/4 full. I check the fuel level sensor - the low side reads 0.00 volts (eg ground) and the high side reads 3.9volts - which seems about right - so that is wierd.

The third picture shows the output from the immobilizer - after I disarmned it (pressed the key for button and got 2 beeps). There is a lot wrong here. The state is immobilized - so the engine definitely won't start with that going on. The doors were all closed and they are shown here as open. The rear lid was open and shows here as closed, the key was is pos ii (run) and shows as off (eg I asked the Galilieo guys and the ignition parameter = key position. The last image shows the immobilizer parameters after I armed the system (eg I presses the key fob button and got one beep) It would appear I've got some kind of electrical issue going on - maybe a bad ground? Not sure. I read anther post where the poster had similar issues and it turned out to be a disconnected ground in the back of his car. Does anyone know where that ground point is? Per the WSM the fuel level sensor, fuel pumps and rear lights have a common ground. I check and the rear lights worked fine. Does anyone have a suggestion on what to look at next? Image Unavailable, Please Login
Maybe the wiring to the inertia switch?

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Look for an earth on pins 85 of relays L & I to see if the inertia switch is providing a (no crash) signal. (I mean check the contacts of the relay sockets which correspond to relay pins 85)

Did you recheck the fuel pressure at the rails?

To bypass inertial switch control, you can jump the relays (L & I) which the inertia switch controls or jump the inertia switch itself. I'm not sure of the pin numbering on the inertia switch (some have 3 pins, others have six), so jumping relays L & I may be best. i.e. pins 30 and 87.

I don't know about anyone else, but I'm having difficulty reading the text in your photos.

 

Ground "305" is the one for the pumps and fuel quantity sender, but it's not shown in the WSM graphics. The equivalent 456M earth is shown to the right of the fuel tank, but nothing is shown in a similar location in the 550 manuals.

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Does the Galileo work with the ignition OFF? I thought you'd at least need ignition power? For some data, you'll need to run the engine... but there is not much you can do about that

 

Relays L & I shown here... but I don't understand why your engine would even run for 2 seconds with the inertia switch activated.

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Quavion - thank you for the reply. Galileo Tech supt tells me that the ignition signal = key position. When the screen shot you asked about was taken the key was in position 2 = run. Also, note that same parameter within the instrument cluster = on. So, what the immobilizer is reporting is wrong. I don't understand why the car starts at all either. It only does it if I leave the car alone for a while (>10+ minutes - I've not timed it). Aside from that the car just turns over and the injectors do not do anything. Re the fuel pumps what I expect them to do is to bring the pressure up when the car runs briefly and then not run at all. I'll see - one thing I'll need to do is bleed the pressure off after it runs briefly - not sure I've done that before (with the injectors not doing anything the pressure will stay up if the pumps run even briefly).

Thanks for the 456 diagram - my car has cables going into that area that appear to dead end.

I will do what you suggested re bypassing the inertia switch and see what happens. I also think I will alternately short and open the fuel level sensor connector and see what that does. I've done that before and the gauge operated properly telling me the wiring is ok.

The Galileo Tech Support person thinks that my issue is a bad instrument cluster and that it might be feeding the immobilizer bad data. Interesting that the data flows that way. I've got more work to do before replacing parts.

I apologize for the screen shots being so small and hard to read. My email is [email protected]. If you will send me an email I will send those pictures directly to you - at full size they should be readable.

Thx

Rodger

 

It's probably easier just to make sure you have an earth on pin 85 of the I and L relays. i.e. standard running configuration. I doubt both relays are not working.

Can you see the RH coolant temperature sensor on your scanner? There was an interesting comment in the WSM regarding fuel injection, initial cranking and coolant temperature:

https://www.ferrarichat.com/forum/posts/149175655/

I can't think of any data that the Immobiliser would need from the instrument cluster. Are they even connected? I can't see any connection in the wiring diagrams.

 

Note that on 550s, she will not even turn over if the immobilizer is active.

 

Good point.

Having said that, there have been some odd defects on the 360 which seemed to allow cranking, but no fuel when the immobiliser has been (apparently) disarmed. There are different output wires from the Immobiliser ECU to the start relay and the RH Motronic ECU (and different Immobiliser internal circuits for that wiring). Of course the circuits in the RH Motronic ECU could be faulty. The RH ECU also has to send an unlock signal to the left ECU. I'm wondering what would happen if one bank was unlocked, but not the other.

At this point, I don't trust those Leonardo readouts, but it wouldn't hurt to check the easy stuff (e.g. the inertia switch circuits)

 

Qavion - for both relays I and L pin 85 is grounded. Re fuel pressure: I tried to start the car - it fired up for a couple of seconds died and fuel pressure was up on the left bank. I bled the pressure off to 0 and attempted to restart the car. It did not fire and the pressure for the left bank came up to 50psi. Same with the right side. Re the temp sensors - the only thing I was able to pull up was engine temp - which was 28C and about right. Image Unavailable, Please Login

Attached is a diagnostic screen shot from the immobilizer. It lists 4 errors: checksum eprom 0110, ECU interface 0101, ECU interface 0102, connection to motronic 0108. Hopefully the Galileo guys can tell me what those errors mean. I know what a checksum error normally indicates. Also I pulled up some internal parameters for the instrument cluster and though the gas gauge said zero - the parameter said 16 liters (which is about right I think). And then I watched it slowly go down from 16 to 8. The gas tank picture (without a line though it) is showing up on the dash at the same time.

What I'm seeing are internal error in two systems. I'd doubt they are both bad - still thinking maybe I have a bad ground somewhere.

 

Here in Australia the name of this sort of product is so hard to forget.
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Coincidentally, I have a can of that in my garden shed. Not sure if I would use it on my car, tho'

Well, that's eliminated the inertia switch as a cause... and all the other things sound ok. I believe the 550 is similar to my F355 (5.2) with regards to the immobiliser. The fuel pump primes even with the immobiliser armed. It's what happens after that is immobiliser-controlled.

Maybe there is a wiring issue between the Immo ECU and the RH Motronics ECU (or the electronics at either end). Unfortunately, not only is the Immobiliser ECU hard to get to on your car, tracing the wiring between them can be tricky as all the security wires are deliberately coloured black. There is also an immobiliser interface unit between them to complicate the issue. Even with the wiring diagrams, the circuits are hard to follow.

I can post the wiring diagram here and guide you through them, but you'll have to pull your car to pieces.

 

On some of these F cars, the fuel quantity is sent to the Motronic ECUs to inhibit certain engine fault messages when the fuel quantity is low. The engine ECU just assumes the misfires, etc, are caused by lack of fuel rather than a real engine problem. I believe on the 550 that the instrument panel processes the fuel quantity transmitter information and sends the data on to the RH ECU. However, it seems unlikely that this data would be used to inhibit the fuel injectors.

 

Coincidently, the Gailieo Tech folks are saying the same thing: " All the errors that you have on Immobilizer may be attributable to wires or connections problems.
I suggest to check the wires from Immo to Engine module. Maintain me informed." I really did want to go there - for the reasons you explained. My understanding is that I'm going need to pull out the passenger seat to get to the immobilizer.

I think I'm going to try one more thing: if I short or open (can't remember which) the connections to the fuel level sensor I can "trick" control logic into thinking there is a full tank of gas -just in case there is some kind of shut down/inhibit feature in the event of an empty gas tank. It's easy to do.

I may likely need those wiring diagrams you mentioned. One thing that I'm wondering about is the Eprom checksum error should not have anything to do with an I/F connection - eg that is all internal to the immobilizer box. What might affect that though is the power or ground. Do you know where some points are to check in that regard (before I start taking things apart)? I'm still thinking that the issues I'm having with fuel level gauge and immobilizer are somehow connected - they all started around the same time.

 

I don't have any specific resistance values for the 550 regarding fuel quantity, but the principle of "zero ohms = full tank" on the F355 may apply to the 550.

The values for the F355 are:

full is zero ohms
light on at 270
empty 330

I would insert a resistance value of something between a short circuit and 270 ohms. If you insert the resistance at the sender unit, that should check all the wiring. If you get a solid reading, it may mean that the sender is faulty.

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Jut put a resistance between pin B and C on the connector i.e. across the only two wires on the sender. I don't know if there are any easier points to insert a resistance.

Wiring diagram here for the instruments:

https://www.dropbox.com/t/p7B2sh9ebz1FHYcf

Same here. Not the best location.

The fuel level sensor is shown in the bottom right hand corner ("125"). Follow the purple (Z) wire to the instrument panel (plug B pin 17). The signal is processed in the "Digitek" display unit and sent to the RH ECU on a white/blue (BL) wire via instrument panel plug C pin 2 and ECU connector 277, mounted just above the ECU itself.

The connector on the RH ECUitself is shown in this diagram:

https://www.dropbox.com/t/CIrdx3svsPTGxVCl

Links expire in 6 days.

Unfortunately, we don't have any detailed wiring harness location diagrams for the 550. Sometimes I can figure it out from photos of the harnesses, but I'm not even sure of the part number for the harness which includes the immobiliser.

The immobiliser diagram is here, but it can be hard to figure out what is what unless you're familiar with the system

https://www.dropbox.com/t/s2Yqn6KJW988LLdq

 

Nick Skidmore may be able to help you with fuel sender resistances. He is now making quality aftermarket senders for Ferraris. He goes under the FChat name @Serious playtime

https://www.ferrarichat.com/forum/threads/550-fuel-tank-sender-units.653531/

I haven't seen him on the forum recently, but I have his email if you can't contact him via the forum.

 

I've highlighted the wires in this alarm diagram which carry the unlock signal from the Alarm ECU to the RH Motronic ECU:

https://www.dropbox.com/t/No8Vyz6WVh2jz1D1

The unlock signal comes from Immobiliser ECU pin 5 of plug B (the 20 pin plug) on a brown/black wire (although I've highlighted it in brown only). Note that pin numbers in the WSM may vary to those numbers embossed on the plugs of the Immobiliser ECU. On my F355, the pin number is 15.

The signal goes to splice "238" where the wire colour changes to black and then to the Alarm Interface Unit "180". I don't know if this is a box of mostly jumper wires or if it has complex electronics inside and signal processing is required. The signal then leaves the Interface Unit and goes to inline plug 277 (pin 20) and then to RH Motronic ECU pin 88.

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The signal is coded, so don't bother looking for a fixed voltage.

Note that a critical earth wire goes through pin 21 of plug 277. I have no idea where that earth is, but you could check that there is an earth on pin 21 (at least on one half of the plug).

There is a chance that simply disconnecting and reconnecting these plugs might fix the problem. Condensation can cause problems in the Motronic ECU areas.