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Discussion Starter #1
hi guys all my respect the lone sheep found the way back since 2009 I have worked wit alfa but not with you now I need your help??? so alfa 166 timing belt gone a 2.0l t spark by the way took a 156 known working engine put in all great except for sump and front mouting swap and then put all electrics earts etc back <not my first engine replace> AND THEN...... car wont start turns over fine all ok but no life from cylinders .now here it is all earths ok and checked,no code light,goes off after 2 sec,i have spark I have fuel in the rail crank sensor already changed due tu suspicion but no start EXCEPT FOR??put petrol in the manifold thrue the injectors holes and starts but not with its own injectors BECAUSE NO petrol coming thru them when crancking and not when actuating them with alfa diag . now there is petrol and pressure in the rail ,it nearly took one eye off me when puling hose out,its start with fuel or easy start in the manifold but no action from the injectors any idea???? please. chris my name by the way. :cry:
 

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Discussion Starter #2
anybody???? well ill add a few details all fuses in the boot checked, all relays pulled out and back, fuel pump works for 3 4 sec every time I switch ignition on, disconnected maf and temp sensor,cranking and NOTHING.only wnen I pour petrol in the manifold or spray easy start ,it fires instantly like a baby.ohh replaced injector rail with injectors as well.i d go for a can of beer but I cant afford it anymore
 

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any electrical supply at the injectors? would suggest a fuse or relay somewhere, there are loads on a 166 dotted all over the place. Do you have access to elearn to see where they all are?
 

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Discussion Starter #4
I have measured the voltage on cranking at the injectors plugs and I get between 0.30 and 0.80 v,should I measure one contact in the plug and earth at the engine?i am just not good with electrics,the ecu is good the old engine worked till the balancer belt wraped around the crank and ripped the timing with it.thanks purple appreciate.
 

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I have measured the voltage on cranking at the injectors plugs and I get between 0.30 and 0.80 v,should I measure one contact in the plug and earth at the engine?i am just not good with electrics,the ecu is good the old engine worked till the balancer belt wraped around the crank and ripped the timing with it.thanks purple appreciate.
Can you measure the voltage between the common injectors wire and chassis (-12V) while trying to start the engine? This voltage should be +12V.
 

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Discussion Starter #6
i try to get hold of elearn like purple 145 was say it but everything online seem to be spam ,and i will chek voltage at in jectors with earth to the engine or chassis ,thanks ecotronic
 

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i try to get hold of elearn like purple 145 was say it but everything online seem to be spam ,and i will chek voltage at in jectors with earth to the engine or chassis ,thanks ecotronic
The common wire of all of the injectors must be supplied with +12V constantly. The invidual injector wires are switched to chassis by the ECU outputs. If for some reason the common wire is not supplied with +12V, the injectors won't work and the measured voltage over them will be something close to 0 V.


Here is the wiring diagram, which may be helpful. I mean the red-marked circuit.
 

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Discussion Starter #8
thanks ecotronic will try that and should i get 12v when cranking? or even with the ignition on? nice to get help from somebody north of danube from where i come.
 

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thanks ecotronic will try that and should i get 12v when cranking? or even with the ignition on? nice to get help from somebody north of danube from where i come.
Yes +12V should be present on the common injector wire while crancking and (I think, but not sure) even with ignition on.

PS:
My location is on the south of Danube :)
 

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Hi, on re-reading your first post, it will not be what I suggested as the starter is turning, where the earth strap fails, nothing works in the engine dept, sparks, starter, injectors etc. If the thing goes with Easi start it must surely be fuel supply as you have already deduced.
 

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Discussion Starter #11
thanks purple 145 and you are still right it is, it must be a electrical fault somewhere,ill try ecotronic advice to check the true voltage at injectors tomorrow it just so simple with the 156 that I cant imagine why 166 is so fussy, I give it a new heart after all,AND ECOTRONIC MY APPOLOGIES I am north of the river just I was I a rush to do the top wishbones on my 2.4 sw and the slave cylinder ,made the mistake ,,,,how is your baby limousine by the way I love the glamour of them but still stick with the legend ,THE 156
 

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Discussion Starter #12
ok guys I have a nasty update as I checked the voltage at the injectors today and I am more confused so:pulled all injectors plugs and measured the left and right pins with earth to the head and body here it is: WITH IGNITION ONLY:left pin 0,90v to head and -12,50v to positive + <battery> ,,,right pin0,02v to head and 0,00 to positive WHEN CRANKING:LEFT PIN 0 TO 2,40V ON THE HEAD FLUCTUATING,,,RIGHT PIN 0 TO 2,40V TO HEAD FLUCTUATING should I not get + 12v on ignition to the head as the common wire always supplies that and you earth the voltmeter to head or body??? I only get -12v to left pin when I earth it to the actual positive wich means that on the common wire travel negative <earth> instead of clean +12v? please somebody with electrical experience or having same sort of trouble take this in consideration AFTER ALL THAT WHY WE ARE THE ALFA ROMEO SOCIETY ,TO SHARE TROUBLE AND HELP IFF POSSIBLE ,THANKS IN ADVANCE:(
 

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Discussion Starter #13
PS I can give some help with my 156 s experience and many other for example 3 weeks ago I replaced the 2,4 jtd engine in my sw and aldo everything was set perfect electrics fueling etc the engine will not start on jump leads for 6 hours??? so??some may say ecu,other hp pump ,timing egr valve immobiliser etc BUT the answer is so simple and it start with digit 2. I have that answer if anybody needs it.
 

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The body and the engine are -12vdc, the injector connector will have two wires - one will +12vdc the other one will be switched -12vdc (injector on off signal)

Ignition on

To determine which wire is the +12vdc attache the black lead from the multimeter to the engine / body of the car now put the red lead on one of the contacts of the connector. When the meter shows +12vdc you have found it. The other one will be zero.

Now leave the red lead on the +12vdc contact and remove the black lead from the body attache it to the other contact.

Cranking the engine

If you have a digital multimeter you may have to set it a lower vdc range then 12 or 24 dependant on the meter because the injector switched -12vdc will very fast and not there for very long ie on -off on - off etc when cranking the engine. If you have multimeter with a analogue sweeping arm you can see this more easily.


Repeat for each injector connector.
 

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ok guys I have a nasty update as I checked the voltage at the injectors today and I am more confused so:pulled all injectors plugs and measured the left and right pins with earth to the head and body here it is: WITH IGNITION ONLY:left pin 0,90v to head and -12,50v to positive + <battery> ,,,right pin0,02v to head and 0,00 to positive WHEN CRANKING:LEFT PIN 0 TO 2,40V ON THE HEAD FLUCTUATING,,,RIGHT PIN 0 TO 2,40V TO HEAD FLUCTUATING should I not get + 12v on ignition to the head as the common wire always supplies that and you earth the voltmeter to head or body??? I only get -12v to left pin when I earth it to the actual positive wich means that on the common wire travel negative <earth> instead of clean +12v? please somebody with electrical experience or having same sort of trouble take this in consideration AFTER ALL THAT WHY WE ARE THE ALFA ROMEO SOCIETY ,TO SHARE TROUBLE AND HELP IFF POSSIBLE ,THANKS IN ADVANCE:(
You have to determine which is the common injectors wire first.
To do this:

1 - Disconnect the battery
2 - Disconnect all the injector plugs
3 - With a multimeter (in ohmmeter mode) measure the resistance between the injector wires of 2 different injectors.

Suppose that the injector wires are marked as: 1a, 1b (the wires of the first injector).....2a,2b the wires of the second one..........etc.
When measuring this resistance, try all of the possible combinations: 1a - 2a; 1a - 2b; 1b - 2a; 1b - 2b.
Doing this, you will get a resistance very close to 0 ohms in only one of the four possible combinations.
Suppose that this combination is 1a - 2a. - that mean - the common wire for injector 1 and 2 is this one (1a for injector 1 and 2a for injector 2)
It is not necessary to do other measurements, because you already found which is the common wire.

4 - plug back the injectors connectors
5 - attach the battery
6 - put the multimeter to voltmeter mode and connect the black lead to chassis
7 - connect the red lead to the injectors common wire and crank the engine

You should get +12V in this situation.

Tell us the result.


BTW - according to the documentation, the common wire should be attached to pin 1 of the injector connector, as shown here.

So you can skip points 1 - 5 and jump directly to point 6


PS:

I'm not sure that i've been clear enough because of my language skills:)
 

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Discussion Starter #16
thanks paul and ecotronic I have determine already the common wire as I shown above it is the left pin as you take plug out BUT problem is with ignition on and multimeter earth to head body I get 0,90v to the left no 1 pin,and between 0 to 2,40v on cranking to the same pin,,the only time I got 12v to left no1 pin it is on ignition and with multimeter earth it to positive lead from battery and it is actually -12v.so is it possible that the common wire is short to the ground somewhere? or the ecu is shot?wich ecu was working till t belt shredded and wreked the valves.again thanks allot for your help.
 

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thanks paul and ecotronic I have determine already the common wire as I shown above it is the left pin as you take plug out BUT problem is with ignition on and multimeter earth to head body I get 0,90v to the left no 1 pin,and between 0 to 2,40v on cranking to the same pin,,the only time I got 12v to left no1 pin it is on ignition and with multimeter earth it to positive lead from battery and it is actually -12v.so is it possible that the common wire is short to the ground somewhere? or the ecu is shot?wich ecu was working till t belt shredded and wreked the valves.again thanks allot for your help.
It seems the missing +12V on the common wire to be the problem with the engine.
You have to locate the relay (J10) and the fuse (B41) for this cirquit.
See the diagram.

First check the fuse. If the fuse is OK, measure if +12V are present on the relay's pin 87. (12V between chassis and pin 87).
 

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Discussion Starter #18
thanks ecotronic tomorrow I ll check that at the moment I ve come from ti autos trak day and seen couple v6 s2,5 and 3,2l I am still in emotional shock,it was a lovely day in Dublin today anusual do and the couple 166 did well aldo the 2 gta 1960 and 2003 took my heart especialy the 156,,,,i want one and my wife thinks I am joking:confused:but I am NOT
 

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Discussion Starter #20
Just in case you where wondering what it was? well a FUSE.here is the story.under plastic cover of the wipers as ecotronic was suggesting from right to left the third 3 relay wich I suppose is the injector relay was missing its fuse:confused: the fuse guard was there but no fuse?:confused: NOW how did the old engine worked without the fuse?the owner my friend did not even knew about the place so?sabotage??? the car was sitting there for about 8 months without a engine under the bonet and the neighbours was complaining about it so?i don't really know if that fuse was removed or was never there in wich case how the old engine worked? I replaced the engine 2 weeks ago and would not start aldo everything was fitted the right way so either the fuse vanished by a miracol or it was pulled out by somebody.ps aldo it is bothers me I am happy that engine started it is snoring like a cat and now I am ready to put a new timing belt in it,thank you all:thumbs:
 
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