dudlington
Tearing my hair out here.................have tried everything but still nada.......... I,m clearly missing something but I,ll go through what I have done already.
Built a main wiring loom for my 888 SP4 project as I could not find/buy one. Checked it against an unmodified Strada loom and all seems good (Apart from 2 injector/4 injector differences off course). I used my running SP4 to check that the wires were all good.. Now it does not matter which main loom I use on the project I get no spark and no fuel. I have swapped all the controls , relays , sensors , recitifier , coils , plugs , leads , ECU , spark plugs with the running bike and all the components are good. Checked for bad earths on all components but all good. Good bike still good(With swapped parts) , bad bike still same symptom. Power comes on to the fuel pump for 5 seconds to prime and then silence...........no spark , no fuel pump noise. Everything else on the project bikes works as it should...........what am I missing here ?. There is no alarm , using a car battery so for sure have enough juice. Both plugs are out but nada from either. Any good advice/help will be appreciated.
marvin
I honesty don't know. But the fuel pump is supposed to only prime, then shut off.
brad black
kill switch on?
it won't do anything until it gets rotation sensor signals. are you getting anything out of them?
stafford
Do you have the correct chip in the ECU for the injector set up? 2 or 4?
dudlington
kill switch on.................Yes. Switching it on and off has the relays in the back clicking so I,m sure it is working (Compared to my working SP4 it is the same).
it won't do anything until it gets rotation sensor signals. are you getting anything out of them? ........................The rotation sensors have been swapped to another working bike and all was good. The bike was previously running albiet with a bastardized racing loom in it that I have now used to bring back to standard. I have of course added the other looms for all the street stuff but everything seems to work just no spark or fuel. I even took the rotation sensors out and removed the shim..........NADA. How can I check those babies on the bike with a meter or a measurement caliper ???.
Do you have the correct chip in the ECU for the injector set up? 2 or 4?..........................The ECU (P7) was originally powering this bike with 4 injectors but I have no idea what is inside. I have also swapped the ECU,s from 2 other working bikes (P7 and P8)............again NADA. It must be ignition from one of the extra cable harnesses I added for all the street stuff. I will swap cable harnesses from the working bikes and see if something happens. Side stand wire is also earthed...........It is painfull but needs must. If anyone can think of anything , any help is appreciated.
mikesps
Have you checked the connectors at the fuse box and relays? They can slip down inside the body and not make contact. Fuses on the relays making good contact?
Mike
stiglarsenDK
missing cross checking some parts from project bike... ?
dudlington
Have you checked the connectors at the fuse box and relays? They can slip down inside the body and not make contact. Fuses on the relays making good contact?...............yes checked all of that.
Today I spent the whole day checking my cable harness against 2 other harnesses (One from a working bike) to make sure it was made correctly. 95% there and all good so far.
I have checked all the obvious things but I,m really after some technical know how to check dimensional things and electrical things............it must be simple !!!!!.
erthmvr888
I had the similar experience on my 1990 851 with s4 harness after some hair pulling it was a bad ground on the ECU
Trav
griff851
I'm with Trav on the bad earth. There's no spark because the rotation sensors aren't getting power. The fuel pump ran for a bit, but stops, so there is power getting to the ecu and fuel circuit. The ecu is the common denominator. Power goes from negative to positive so as soon as there is current something gets a little hot resistance goes up, ecu goes no power, all stop. It's a quick check, just by pass the ecu case with a bit of wire. Then with the cover of the ecu plug off, by pass the earths until you find which one.
dudlington
So here goes :
Right track on the computer Earthing so thanks guys for suggesting it. I had checked it before with my trusty bulb but clearly it breaks down with resistance.
BUT there is more as I have no fuel still !!!!!!.
Full story from today :
Put a seperate earth on the P7 computer that I got with the bike and then I got a fat healthy spark on both cylinders.............Result so much further.
Replaced the ECU for a P8 computer from a working bike and checked the voltage on each injector when Ignition on/starting the bike . Inj 1 only max = 5 volts , inj 2,3 and 4 = 12/13v.
Now I still have no fuel so checked the fuel pump............crappy connection inside the tank but fixed now and all works. Turn on ignition , pump engages for 5 secs and then turns off. When you push the starter you can hear the pump re-engaging................now it gets interesting. No fuel on other side of fuel regulator , replaced with another from a working bike..............still nothing at the other side of the regulator.
So saw another thread and had the mindset around the wrong way for the fuel.
Should be : pump > filter > injectors > regulator > low press return to tank. I had it the wrong way around.
Bike now fires up but something is wrong (Probably inj 1 not getting enough voltage). I even tried the old P7 computer that came with the bike and it runs the same.........slightly uneven.
Had some luck............notice fuel dripping onto the exhaust (Clamp not tightened enough) so it could have all ended in tears. Bike cooling down now. Even though I have checked the connection to inj 1 to pin number 32 of the ECU , I will try and run another seperate line to see if it can get the voltage up to the same as the other ones.
Still need help.............learning all the time.
griff851
Just off to the printers to get your Ducati mechanics certificate done.
3 our of 4 isn't bad. 😄 Could be a duff injector. We're they serviced, could be gummed up. Sometimes a little tap unsticks them. Fuel injector cleaner might free it up, certainly won't hurt. If not pull the injector (second hardest job in the universe as the suckers are in tight) and get it cleaned. You can do it your self with a battery and some tube filled with Freon or acetone (be quick and have petrol on hand to rinse) an injector is a solenoid valve that cycles quickly that uses fluid to cool itself.)
dudlington
What I have found out now is..............I have +12v on all injectors...........seems like a dodgy connector on pin 32 in the connector block (I will replace tomorrow). Seems like the common brown wires for all injectors have the voltage from the relay when the ignition is on but also the coloured wire picks up the voltage and sends it back to the ECU for processing.................sound about right or is this a sign they are stuck ???. My problem is the bike still sounds and feels like it is not running properly. I wonder if I have to strip the injectors and give them a clean (9v battery and carb cleaner) as the last time the bike ran it was over 5 years ago. Using the P7 computer or P8 computer makes no difference to the running.
Any ideas ?????????????????.
P.S. At least it is running now.
Certificate..........Ducati Mechanic ............... Just a guy in his garage learning everyday.
marvin
I clean injectors with Chevron full system cleaner. I rigged up a system using a momentary switch connected to a 12V supply. A fuel pump is great but you don't really need all that much pressure to clean the injectors.
griff851
Don't use carb cleaner. Nasty shit. Acetone works way better. I did one with carb cleaner and all the Black came off the injector. Try that injector cleaner you put in your tank and run it for a bit first. KISS.
I use to use carb cleaner to de-coke heads and pistons and clean green death out of carbies until I discovered using acetone and the crap just wipes off. It also doesn't burn your skin, and leave a nasty taste in your mouth from the vapours. I use a well ventilated area and a have a fan lightly blowing over the area where I work so the acetone doesn't get to me.
brad black
the wires from the ecu to injector are simply earths to switch the injector on. if there is voltage in one of those wires there's something wrong. swap the injector connectors around and see if the voltage issue follows the injector.
or unplug the injector and see if it is still there.
well, thinking about it, they'd all have 12v at the ecu end with the bike not running and ign on, as it'll just be feeding the unloaded potential voltage through the injectors. earth them out tho and the injectors should open and the voltage should go to 0.
if there is voltage there (and it should also have an ac component if it is running) it must have another current draw in that circuit.
dudlington
So thanks for all the help guys. Bike starts and ticks over but I,m running a top off airbox and it seems like it is getting either too much air or not enough fuel. I am running a P7 computer and have also tried 2 P8 computers from other bikes...........still does not sound right. Giving it gas just does not seem to spin up the engine fast enough. I,m going to run some cleaner through it and see what happens. Maybe the injectors clear themselves or maybe I just take it to a Ducati guy I know for a second opinion. I will also tape up the airbox to restrict the air to see if anything happens......... The thing was it was running before with a heavily bastardise wiring loom (And other crazy/crappy stuff) so I a bit at a loss for more to do. Any advice on easy stuff to check would be appreciated.
dudlington
So I have stripped the injection system down and left it all for the last 2 days in acetone , re-fitted and have now a big improvement. On low to medium gas you can see the 2 injectors working and then full gas all 4 injectors working (P7 computer). It will rev to 10,000 rpm but I still get the feeling it needs probably another chip in it. I,m running a complete cutoff the top air filter box with a K and N filter and full race Termignoni,s. I will search for a +5% chip and see if that helps. The tip with the Acetone from Griff 851 (Nail varnish remover was a good one and really cheap) so thanks for that.
griff851
Probably works fast with a tubed filled stuck on the injector and a battery. But if you get a spark.......... bye bye eye brows.😁
Check out the color of your pipes, and adjust the trim on the ecu and see if that helps.
