Injectors not firing - why?

[LanciaNut69]

Chaps,

Wonder if you can help out here or offer some suggestions/pointers to solve this issue.

Basically she will start using the cold start valve, but the injectors do not seem to be firing.  I have checked continuity of all wiring to the various injectors and sensors.  I have also checked resistance on the senders and the injectors - all ok.  The TPS has been adjusted correctly and whilst the regulator will not hold the fuel pressure when the engine is switched off in the long term - it does hold 40 PSI when the injection is switched on. 

The injectors do give a spray pattern when they are powered. 

Spark plugs are new, as are HT leads and rotor arm.  There are sparks when turning over.  Injection system earths have been cleaned and refitted to cam box.

Aux air valve appears to be working and does open and close, temp depending.  Cold start valve activates and shuts off correctly.

AFM appears to be working properly.

Brake servo hose and non return valve have been replaced.  Ignition switch has been replaced and does require a positive action to get the ignition lights on, but given that it has run, I don't think it's preventing starting, although should be replaced at a later date.

I'm coming round to thinking that it's ECU related, unless anyone has any ideas?

Thanks in advance and look forward to hearing from you!

Cheers

Darren

[Thotos]

I believe the Beta injection system (Bosch L-Jetronic) is the same as on the Gamma. The injectors all fire at the same time (i.e. non-sequential) and the trigger comes from the firing side of the coil. In the Gamma there's a wire that runs from the coil to the ECU and it has an in-line fuse. If the fuse has blown or there are bad connections to the fuse holder then the injectors will never fire.

[LanciaNut69]

Hi Theo,

Yes, that is correct - there is a fuse off the double relay I think that powers the injectors.  They are then switched by the ECU on the earth side.  There is power getting to the injectors I think, but there does not appear to be the instruction from the ECU with the earth signal.  I have ordered a noid light so I'll be able to check for sure.

Just reread and will look to see if there is a fuse between the positive side of the coil and the ECU.

Thanks for the pointer!

Cheers

Darren

[Thotos]

The wire is from the -ve (firing) side of the coil to the ECU and it's what tells the ECU to fire the injectors. As I said above, all 4 injectors fire at the same time. The ignition unit tells the coil to fire the spart plug and the same signal tells the ECU to fire the injectors. The potentiometre in the air metering box tells the ECU how much air is being sucked by the engine and the ECU uses this plus the signal from the water temperature sensor to determine how long the injectors should be kept on for. I think most likely your problem will be a connection problem to one of the places where the ECU gets a signal from.

[LanciaNut69]

Hi again Theo,

Sorry for being a bit dense there - I blame vino! ;o)  I'll revisit the coil connections and report back!

Cheers

Darren

[LanciaNut69]

Right, next update - I have the following connections at the coil

Pin 1 (-ve) black shielded wire, and two red/green trace wires.
Pin 15 (+ve) Blue/black trace and a red/black trace.

Shielded wire speaks for itself.  The red/green goes back to the twin relay pin 9 in part and presumably to the ECU for the other wire - will trace this.  I have continuity from twin relay to coil on this and to earth.

Blue/is IGN switched live and black/red runs to twin relay pin 1.  I have checked the other wires from this side of the relay and confirm I have the correct voltages and trigger for the fuel pump. 

More info to follow after lunch!

Cheers

Darren

[LanciaNut69]

Have now checked through to trace the red/green trace wire and have 2 running to the negative terminal of the coil.  One runs, as per last post to pin 9 of the IGN side of the twin relay.  The other runs to the digiplex unit, via a three pin connector.  This has a blue/white trace and a black.  This plug connects black to black, blue/white to blue/white, and red/green to grey.  This grey wire is a switched live.  

The other red/green runs from this 3 way, up to the digiplex plug at number 4 or 8 depending which way you look at it.

All fuses in fuse box are unbroken, fuel pump still running, got sparks, got cold start valve working as it should, but still nothing from the injectors.

Any suggestions, or anyone got an ecu I can borrow?

Cheers

Darren

[Thotos]

I have a spare Gamma ECU which is most probably the same. Where are you based?

[rossocorsa]

I might have a spare one somewhere there are two different ecu for betas depending on the ignition system so I could have a look but would need to know which part number is on yours

[LanciaNut69]

Thanks guys, I'll get the info and come back to you.  I'm South based, halfway between Newbury and Basingstoke.

Cheers

Darren

[LanciaNut69]

ECU now out - Bosch 0 280 000 174

Keeping finger crossed one you you chaps can help!

Incidentally, is there a complete 'proper' wiring schematic for the ie Betas?  I've got the pin out diagram for the ecu, together with twin relay wiring, but nothing for the rest of the car, including the digiplex unit.

Cheers

Darren

[peteracs]

Hi Darren

There is a US centric version for the 81 model year on the Lancisti site in the download section which may help?

Peter

[rossocorsa]

there is one need to check where I have it

[rossocorsa]

https://www.dropbox.com/s/pvb2rl6e6b4twrd/Beta%20coupe%20hpe%20series%202%20fl2%20electrics.pdf?dl=0

Not the best quality but better than nothing! If there is anything missing let me know as I have the L jetronic manual as well

[LanciaNut69]

Hi Peter,

Thanks for that - will have a look, but I don't think its the same as UK cars, as they were confused when I was talking about crank senors, etc.

Cheers

Darren

Hi Darren

There is a US centric version for the 81 model year on the Lancisti site in the download section which may help?

Peter

[LanciaNut69]

Thanks for that, much appreciated - I'll have a delve through it while waiting to see if anyone has a working ECU I can borrow.

Cheers,

Darren

https://www.dropbox.com/s/pvb2rl6e6b4twrd/Beta%20coupe%20hpe%20series%202%20fl2%20electrics.pdf?dl=0

Not the best quality but better than nothing! If there is anything missing let me know as I have the L jetronic manual as well

[thecolonel]

I have a couple on the shelf (southampton) both from 'Y' Reg cars.
I also have the injector engine bay loom, relays and injector rail.
Plus airflow meters.

[LanciaNut69]

Hi Geoff,

PM sent 👍👍

Cheers

Darren

I have a couple on the shelf (southampton) both from 'Y' Reg cars.
I also have the injector engine bay loom, relays and injector rail.
Plus airflow meters.

[gengis]

Just for info, I have a couple of ECU's one from a Coupe ie, and one from a HPE ie and both are marked with the part No..0 280 000 216. 

I wonder if the ECU you have is designed to fire injectors with a higher impedance, therefore firing your lower impedance injectors has burned out the injector drivers?

I can send you a ECU, if you don't manage to get one.

[LanciaNut69]

Hi Gengis,

Thanks for that - is that the difference between the two ECU codes?  In typical Lancia fashion, both 174 and 216 are listed for cars 81-84, with 174 being applicable to 1980 cars.  This one is on an 'A' plate, so 83/84.

Is there a way to tell high impedance injectors from low and which belong to which ECU? 

Geoff is very kindly looking out a unit for me to test, but if I can keep you on standby if I need the 216, that would be great 👍👍

Thanks again guys

Darren

Just for info, I have a couple of ECU's one from a Coupe ie, and one from a HPE ie and both are marked with the part No..0 280 000 216. 

I wonder if the ECU you have is designed to fire injectors with a higher impedance, therefore firing your lower impedance injectors has burned out the injector drivers?

I can send you a ECU, if you don't manage to get one.